diff --git a/backend/src/routes/auth/auth.service.ts b/backend/src/routes/auth/auth.service.ts
index 423b9b4..bfbd28e 100644
--- a/backend/src/routes/auth/auth.service.ts
+++ b/backend/src/routes/auth/auth.service.ts
@@ -36,6 +36,7 @@ import { MailService } from 'src/modules/mail/mail.service';
 import { ParentsService } from '../parents/parents.service';
 import { DossiersService } from '../dossiers/dossiers.service';
 import { DossierAmCompletDto } from '../dossiers/dto/dossier-am-complet.dto';
+import { StaffAddCoParentDto } from '../parents/dto/staff-add-co-parent.dto';
 
 @Injectable()
 export class AuthService {
@@ -718,6 +719,167 @@ export class AuthService {
         });
     }
 
+    /**
+     * Ajoute un co-parent à un foyer existant (mono-parent) — ticket #135.
+     * Compte actif + mail création MDP + liens Parents bidirectionnels + enfants du foyer.
+     */
+    async addCoParentStaff(pivotUserId: string, dto: StaffAddCoParentDto) {
+        const pivotParent = await this.parentsRepo.findOne({
+            where: { user_id: pivotUserId },
+            relations: ['user', 'co_parent', 'parentChildren'],
+        });
+        if (!pivotParent?.user) {
+            throw new NotFoundException('Parent introuvable');
+        }
+
+        if (pivotParent.co_parent) {
+            throw new BadRequestException('Ce foyer a déjà un co-parent.');
+        }
+
+        const numeroDossier = pivotParent.numero_dossier?.trim() || pivotParent.user.numero_dossier?.trim();
+        if (!numeroDossier) {
+            throw new BadRequestException("Ce parent n'a pas de numéro de dossier.");
+        }
+
+        const sameDossierCount = await this.parentsRepo.count({
+            where: { numero_dossier: numeroDossier },
+        });
+        if (sameDossierCount >= 2) {
+            throw new BadRequestException('Ce dossier a déjà deux responsables.');
+        }
+
+        const email = dto.email.trim().toLowerCase();
+        if (pivotParent.user.email.trim().toLowerCase() === email) {
+            throw new BadRequestException(
+                "L'email du co-parent doit être différent de celui du parent principal.",
+            );
+        }
+
+        const emailExiste = await this.usersService.findByEmailOrNull(dto.email);
+        if (emailExiste) {
+            throw new ConflictException("L'email du co-parent est déjà utilisé");
+        }
+
+        const memeAdresse = dto.meme_adresse ?? true;
+        if (!memeAdresse) {
+            if (!dto.adresse?.trim() || !dto.ville?.trim() || !dto.code_postal?.trim()) {
+                throw new BadRequestException(
+                    "Adresse, code postal et ville du co-parent sont requis si meme_adresse est faux.",
+                );
+            }
+        }
+
+        const joursExpirationToken = await this.appConfigService.get<number>(
+            'password_reset_token_expiry_days',
+            7,
+        );
+        const tokenCreationMdp = crypto.randomUUID();
+        const dateExpiration = new Date();
+        dateExpiration.setDate(dateExpiration.getDate() + joursExpirationToken);
+
+        let coParent: Users;
+
+        try {
+            coParent = await this.usersRepo.manager.transaction(async (manager) => {
+                const pivotUser = await manager.findOne(Users, {
+                    where: { id: pivotUserId },
+                });
+                if (!pivotUser) {
+                    throw new NotFoundException('Parent introuvable');
+                }
+
+                const pivotEntite = await manager.findOne(Parents, {
+                    where: { user_id: pivotUserId },
+                    relations: ['parentChildren'],
+                });
+                if (!pivotEntite) {
+                    throw new NotFoundException('Parent introuvable');
+                }
+
+                const coUser = manager.create(Users, {
+                    email: dto.email.trim(),
+                    prenom: dto.prenom,
+                    nom: dto.nom,
+                    role: RoleType.PARENT,
+                    statut: StatutUtilisateurType.ACTIF,
+                    telephone: dto.telephone,
+                    adresse: memeAdresse ? pivotUser.adresse : dto.adresse,
+                    code_postal: memeAdresse ? pivotUser.code_postal : dto.code_postal,
+                    ville: memeAdresse ? pivotUser.ville : dto.ville,
+                    token_creation_mdp: tokenCreationMdp,
+                    token_creation_mdp_expire_le: dateExpiration,
+                    numero_dossier: numeroDossier,
+                });
+                const coUserSaved = await manager.save(Users, coUser);
+
+                pivotEntite.co_parent = coUserSaved;
+                pivotEntite.numero_dossier = numeroDossier;
+                await manager.save(Parents, pivotEntite);
+
+                const coEntite = manager.create(Parents, {
+                    user_id: coUserSaved.id,
+                    numero_dossier: numeroDossier,
+                });
+                coEntite.user = coUserSaved;
+                coEntite.co_parent = pivotUser;
+                await manager.save(Parents, coEntite);
+
+                const enfantIds = (pivotEntite.parentChildren ?? [])
+                    .map((pc) => pc.enfantId)
+                    .filter(Boolean);
+                for (const enfantId of enfantIds) {
+                    const existing = await manager.findOne(ParentsChildren, {
+                        where: { parentId: coUserSaved.id, enfantId },
+                    });
+                    if (existing) continue;
+                    await manager.save(
+                        ParentsChildren,
+                        manager.create(ParentsChildren, {
+                            parentId: coUserSaved.id,
+                            enfantId,
+                        }),
+                    );
+                }
+
+                return coUserSaved;
+            });
+        } catch (err) {
+            if (this.isPostgresUniqueViolation(err)) {
+                throw new ConflictException(
+                    'Un compte avec cet email existe déjà (contrainte unique en base).',
+                );
+            }
+            throw err;
+        }
+
+        try {
+            await this.mailService.sendValidatedAccountPasswordSetupEmail(
+                {
+                    email: coParent.email,
+                    prenom: coParent.prenom ?? '',
+                    nom: coParent.nom ?? '',
+                    token: tokenCreationMdp,
+                    numeroDossier,
+                },
+                'parent',
+            );
+        } catch (err) {
+            this.logger.error(
+                '[addCoParentStaff] Échec envoi email création MDP (co-parent conservé)',
+                err instanceof Error ? err.stack : String(err),
+            );
+        }
+
+        return {
+            message:
+                'Co-parent ajouté au foyer. Un e-mail de création de mot de passe a été envoyé.',
+            numero_dossier: numeroDossier,
+            parent_user_id: pivotUserId,
+            co_parent_user_id: coParent.id,
+            statut: StatutUtilisateurType.ACTIF,
+        };
+    }
+
     /**
      * Cœur partagé création dossier AM (#156).
      * - public : statut en_attente + mail pending
diff --git a/backend/src/routes/enfants/enfants.controller.ts b/backend/src/routes/enfants/enfants.controller.ts
index 492c885..8b44228 100644
--- a/backend/src/routes/enfants/enfants.controller.ts
+++ b/backend/src/routes/enfants/enfants.controller.ts
@@ -141,12 +141,20 @@ export class EnfantsController {
     RoleType.GESTIONNAIRE,
   )
   @Patch(':id')
+  @ApiOperation({
+    summary: 'Mettre à jour un enfant',
+    description:
+      'JSON sans photo OK ; avec nouvelle photo → multipart (champ fichier `photo`, max 5 Mo).',
+  })
+  @ApiConsumes('application/json', 'multipart/form-data')
+  @UseInterceptors(OptionalEnfantPhotoInterceptor)
   update(
     @Param('id', new ParseUUIDPipe()) id: string,
     @Body() dto: UpdateEnfantsDto,
+    @UploadedFile() photo: Express.Multer.File,
     @User() currentUser: Users,
   ) {
-    return this.enfantsService.update(id, dto, currentUser);
+    return this.enfantsService.update(id, dto, currentUser, photo);
   }
 
   @Roles(RoleType.SUPER_ADMIN)
diff --git a/backend/src/routes/enfants/enfants.service.ts b/backend/src/routes/enfants/enfants.service.ts
index 4e0d393..43a4861 100644
--- a/backend/src/routes/enfants/enfants.service.ts
+++ b/backend/src/routes/enfants/enfants.service.ts
@@ -195,7 +195,12 @@ export class EnfantsService {
 
 
   // Mise à jour
-  async update(id: string, dto: Partial<CreateEnfantsDto>, currentUser: Users): Promise<Children> {
+  async update(
+    id: string,
+    dto: Partial<CreateEnfantsDto>,
+    currentUser: Users,
+    photoFile?: Express.Multer.File,
+  ): Promise<Children> {
     const child = await this.childrenRepository.findOne({ where: { id } });
     if (!child) throw new NotFoundException('Enfant introuvable');
 
@@ -205,6 +210,13 @@ export class EnfantsService {
       patch.consent_photo = dto.consent_photo;
       patch.consent_photo_at = dto.consent_photo ? new Date() : null!;
     }
+    if (photoFile) {
+      patch.photo_url = `/uploads/photos/${photoFile.filename}`;
+      if (dto.consent_photo !== false) {
+        patch.consent_photo = true;
+        patch.consent_photo_at = new Date();
+      }
+    }
 
     await this.childrenRepository.update(id, patch);
     return this.findOne(id, currentUser);
diff --git a/backend/src/routes/parents/dto/staff-add-co-parent-response.dto.ts b/backend/src/routes/parents/dto/staff-add-co-parent-response.dto.ts
new file mode 100644
index 0000000..6abf6af
--- /dev/null
+++ b/backend/src/routes/parents/dto/staff-add-co-parent-response.dto.ts
@@ -0,0 +1,23 @@
+import { ApiProperty } from '@nestjs/swagger';
+import { StatutUtilisateurType } from 'src/entities/users.entity';
+
+/** Réponse 201 POST /parents/:id/co-parent (#135). */
+export class StaffAddCoParentResponseDto {
+  @ApiProperty()
+  message: string;
+
+  @ApiProperty({ example: '2026-000043' })
+  numero_dossier: string;
+
+  @ApiProperty({ format: 'uuid', description: 'UUID du parent pivot' })
+  parent_user_id: string;
+
+  @ApiProperty({ format: 'uuid', description: 'UUID du co-parent créé' })
+  co_parent_user_id: string;
+
+  @ApiProperty({
+    enum: StatutUtilisateurType,
+    example: StatutUtilisateurType.ACTIF,
+  })
+  statut: StatutUtilisateurType;
+}
diff --git a/backend/src/routes/parents/dto/staff-add-co-parent.dto.ts b/backend/src/routes/parents/dto/staff-add-co-parent.dto.ts
new file mode 100644
index 0000000..0f7345c
--- /dev/null
+++ b/backend/src/routes/parents/dto/staff-add-co-parent.dto.ts
@@ -0,0 +1,69 @@
+import { ApiProperty, ApiPropertyOptional } from '@nestjs/swagger';
+import {
+  IsBoolean,
+  IsEmail,
+  IsNotEmpty,
+  IsOptional,
+  IsString,
+  Matches,
+  MaxLength,
+  MinLength,
+} from 'class-validator';
+
+/**
+ * Ajout d’un co-parent sur un foyer existant (staff) — ticket #135.
+ * Corps sans préfixe `co_parent_*` (l’URL cible déjà le pivot).
+ */
+export class StaffAddCoParentDto {
+  @ApiProperty({ example: 'thomas.martin@ptits-pas.fr' })
+  @IsEmail({}, { message: 'Email invalide' })
+  @IsNotEmpty({ message: "L'email est requis" })
+  email: string;
+
+  @ApiProperty({ example: 'Thomas' })
+  @IsString()
+  @IsNotEmpty({ message: 'Le prénom est requis' })
+  @MinLength(2)
+  @MaxLength(100)
+  prenom: string;
+
+  @ApiProperty({ example: 'MARTIN' })
+  @IsString()
+  @IsNotEmpty({ message: 'Le nom est requis' })
+  @MinLength(2)
+  @MaxLength(100)
+  nom: string;
+
+  @ApiProperty({ example: '0678456789' })
+  @IsString()
+  @IsNotEmpty({ message: 'Le téléphone est requis' })
+  @Matches(/^(\+33|0)[1-9](\d{2}){4}$/, {
+    message: 'Le numéro de téléphone doit être valide (ex: 0689567890 ou +33689567890)',
+  })
+  telephone: string;
+
+  @ApiPropertyOptional({
+    example: true,
+    description: 'Si true, copie l’adresse du parent pivot',
+  })
+  @IsOptional()
+  @IsBoolean()
+  meme_adresse?: boolean;
+
+  @ApiPropertyOptional()
+  @IsOptional()
+  @IsString()
+  adresse?: string;
+
+  @ApiPropertyOptional()
+  @IsOptional()
+  @IsString()
+  @MaxLength(10)
+  code_postal?: string;
+
+  @ApiPropertyOptional()
+  @IsOptional()
+  @IsString()
+  @MaxLength(150)
+  ville?: string;
+}
diff --git a/backend/src/routes/parents/parents.controller.spec.ts b/backend/src/routes/parents/parents.controller.spec.ts
index 0015373..4452cd6 100644
--- a/backend/src/routes/parents/parents.controller.spec.ts
+++ b/backend/src/routes/parents/parents.controller.spec.ts
@@ -11,6 +11,7 @@ describe('ParentsController', () => {
   let controller: ParentsController;
   const authServiceMock = {
     createParentDossierStaff: jest.fn(),
+    addCoParentStaff: jest.fn(),
   };
   const parentsServiceMock = {};
   const userServiceMock = {};
@@ -77,4 +78,27 @@ describe('ParentsController', () => {
     expect(res.enfant_ids).toEqual(['e1']);
     expect(res.statut).toBe(StatutUtilisateurType.ACTIF);
   });
+
+  it('addCoParent delegates to authService.addCoParentStaff', async () => {
+    authServiceMock.addCoParentStaff.mockResolvedValue({
+      message: 'ok',
+      numero_dossier: '2026-000043',
+      parent_user_id: 'p1',
+      co_parent_user_id: 'p2',
+      statut: StatutUtilisateurType.ACTIF,
+    });
+
+    const body = {
+      email: 'coparent@test.fr',
+      prenom: 'Thomas',
+      nom: 'MARTIN',
+      telephone: '0678456789',
+      meme_adresse: true,
+    };
+
+    const res = await controller.addCoParent('p1', body as any);
+    expect(authServiceMock.addCoParentStaff).toHaveBeenCalledWith('p1', body);
+    expect(res.co_parent_user_id).toBe('p2');
+    expect(res.statut).toBe(StatutUtilisateurType.ACTIF);
+  });
 });
diff --git a/backend/src/routes/parents/parents.controller.ts b/backend/src/routes/parents/parents.controller.ts
index 6d821ff..1567509 100644
--- a/backend/src/routes/parents/parents.controller.ts
+++ b/backend/src/routes/parents/parents.controller.ts
@@ -30,6 +30,8 @@ import { UpdateParentsDto } from '../user/dto/update_parent.dto';
 import { UpdateParentFicheAdminDto } from './dto/update-parent-fiche-admin.dto';
 import { StaffCreateParentDossierDto } from './dto/staff-create-parent-dossier.dto';
 import { StaffCreateParentDossierResponseDto } from './dto/staff-create-parent-dossier-response.dto';
+import { StaffAddCoParentDto } from './dto/staff-add-co-parent.dto';
+import { StaffAddCoParentResponseDto } from './dto/staff-add-co-parent-response.dto';
 import { RegisterParentCompletDto } from '../auth/dto/register-parent-complet.dto';
 import { AuthGuard } from 'src/common/guards/auth.guard';
 import { RolesGuard } from 'src/common/guards/roles.guard';
@@ -176,6 +178,28 @@ export class ParentsController {
     return mapParentForApi(parent);
   }
 
+  @Roles(RoleType.SUPER_ADMIN, RoleType.ADMINISTRATEUR, RoleType.GESTIONNAIRE)
+  @Post(':id/co-parent')
+  @HttpCode(HttpStatus.CREATED)
+  @ApiOperation({
+    summary: 'Ajouter un co-parent à un foyer existant (staff) — ticket #135',
+    description:
+      'Foyer mono-parent uniquement. Crée le co-parent actif, liens foyer + enfants, ' +
+      'e-mail de création de mot de passe. Ne pas utiliser POST /auth/register/parent.',
+  })
+  @ApiParam({ name: 'id', description: 'UUID utilisateur du parent pivot' })
+  @ApiBody({ type: StaffAddCoParentDto })
+  @ApiResponse({ status: 201, type: StaffAddCoParentResponseDto })
+  @ApiResponse({ status: 400, description: 'Foyer déjà à 2 parents / validation' })
+  @ApiResponse({ status: 404, description: 'Parent introuvable' })
+  @ApiResponse({ status: 409, description: 'Email déjà pris' })
+  async addCoParent(
+    @Param('id') id: string,
+    @Body() dto: StaffAddCoParentDto,
+  ): Promise<StaffAddCoParentResponseDto> {
+    return this.authService.addCoParentStaff(id, dto);
+  }
+
   @Roles(RoleType.SUPER_ADMIN, RoleType.GESTIONNAIRE, RoleType.ADMINISTRATEUR)
   @Post(':id/enfants/:enfantId')
   @ApiOperation({ summary: 'Rattacher un enfant à un parent — ticket #115' })
diff --git a/docs/tmp/135-contrat-api-ajout-co-parent.md b/docs/tmp/135-contrat-api-ajout-co-parent.md
new file mode 100644
index 0000000..dd47421
--- /dev/null
+++ b/docs/tmp/135-contrat-api-ajout-co-parent.md
@@ -0,0 +1,73 @@
+# Mini-spec API — POST /parents/:id/co-parent (#135)
+
+Contrat back pour l’ajout d’un **2ᵉ parent** sur un foyer mono-parent (staff).
+
+## Endpoint
+
+| | |
+|--|--|
+| **Méthode** | `POST` |
+| **URL** | `{base}/api/v1/parents/{parentUserId}/co-parent` |
+| **Auth** | Bearer JWT |
+| **Rôles** | `gestionnaire`, `administrateur`, `super_admin` |
+| **Succès** | **201** |
+
+`parentUserId` = UUID du **parent pivot** (déjà dans le dossier).
+
+Ne **pas** appeler `POST /auth/register/parent` ni `POST /parents/dossier`.
+
+---
+
+## Body (JSON)
+
+| Champ | Type | Obligatoire | Notes |
+|-------|------|-------------|--------|
+| `email` | string | oui | unique |
+| `prenom` | string | oui | |
+| `nom` | string | oui | |
+| `telephone` | string | oui | `0X…` ou `+33…` |
+| `meme_adresse` | bool | non | défaut **true** → copie adresse du pivot |
+| `adresse` | string | si `meme_adresse=false` | |
+| `code_postal` | string | si `meme_adresse=false` | |
+| `ville` | string | si `meme_adresse=false` | |
+
+---
+
+## Comportement 201
+
+- User co-parent **actif** + token création MDP
+- Fiche `parents` + liens pivot ↔ co-parent + même `numero_dossier`
+- Enfants du foyer rattachés au co-parent
+- E-mail **création MDP** (pas mail « en attente »)
+
+```json
+{
+  "message": "Co-parent ajouté au foyer. Un e-mail de création de mot de passe a été envoyé.",
+  "numero_dossier": "2026-000043",
+  "parent_user_id": "uuid-pivot",
+  "co_parent_user_id": "uuid-co",
+  "statut": "actif"
+}
+```
+
+## Erreurs
+
+| Code | Cas |
+|------|-----|
+| 400 | Déjà un co-parent / 2 responsables / validation adresse |
+| 401 | Token invalide |
+| 403 | Rôle non staff |
+| 404 | Pivot introuvable |
+| 409 | Email déjà pris |
+
+## Réemploi édition identité
+
+| Endpoint | Usage |
+|----------|--------|
+| `GET /dossiers/:numero` | Préremplir wizard edit |
+| `PATCH /parents/:id/fiche` | Sauver identité pivot / co-parent existant |
+| `PATCH /assistantes-maternelles/:id/fiche` | Édition AM |
+
+## Branche
+
+`feature/135-edition-dossier`
diff --git a/docs/tmp/135-mini-spec-front-edition-dossier.md b/docs/tmp/135-mini-spec-front-edition-dossier.md
new file mode 100644
index 0000000..f20113b
--- /dev/null
+++ b/docs/tmp/135-mini-spec-front-edition-dossier.md
@@ -0,0 +1,83 @@
+# Mini-spec front — Mode édition dossier + ajout 2ᵉ parent (#135)
+
+Branche : `feature/135-edition-dossier`  
+Ticket : **#135** (full-stack)
+
+Prérequis : **#153** (liste Dossiers) livré.
+
+---
+
+## Objectif
+
+1. Clic sur un dossier (liste #153) → ouvrir le wizard en mode **`edit`**
+2. Foyer **mono-parent** : page co-parent → **switch** ajouter un 2ᵉ parent
+3. Sauvegarder les champs via APIs existantes + nouvel endpoint co-parent
+
+---
+
+## Modes wizard
+
+| Mode | Famille | AM |
+|------|---------|-----|
+| `review` | déjà | déjà |
+| `create` | déjà (#129) | déjà (#156) |
+| **`edit`** | **à faire** | **à faire** |
+
+Factories : `ParentDossierWizard.edit(...)` / `AmDossierWizard.edit(...)`  
+Préremplir via `UserService.getDossierByNumero(numero)`.
+
+---
+
+## APIs
+
+| Action | Endpoint |
+|--------|----------|
+| Charger | `GET /dossiers/:numero` |
+| Sauver parent | `PATCH /parents/:id/fiche` |
+| Sauver AM | `PATCH /assistantes-maternelles/:id/fiche` |
+| **Ajouter co-parent** | **`POST /parents/:pivotUserId/co-parent`** — voir `docs/tmp/135-contrat-api-ajout-co-parent.md` |
+
+Body co-parent :
+
+```json
+{
+  "email": "thomas@…",
+  "prenom": "Thomas",
+  "nom": "MARTIN",
+  "telephone": "0678456789",
+  "meme_adresse": true
+}
+```
+
+`UserService.addCoParent(pivotUserId, body)` → cet endpoint.
+
+---
+
+## UX
+
+- Depuis `DossiersManagementWidget` / carte liste : clic → edit (plus seulement review pending)
+- Pending : garder validation (review) ; dossiers actifs → edit
+- Mono-parent : switch « Ajouter un co-parent » (comme create) → au save, `POST …/co-parent` si nouveau
+- Déjà 2 parents : éditer les deux fiches ; pas de 3ᵉ
+- Pas de bouton créer dans l’onglet Dossiers
+
+---
+
+## Hors scope
+
+- Famille N responsables (#139)
+- Suppressions (#154)
+- Création dossier initial (#129 / #156)
+
+---
+
+## Critères d’acceptation
+
+- [ ] Clic dossier actif → wizard edit prérempli
+- [ ] PATCH fiche enregistre les modifs
+- [ ] Mono-parent + switch → co-parent créé (actif + mail MDP)
+- [ ] review / create inchangés
+
+## Branche
+
+`feature/135-edition-dossier`
diff --git a/frontend/lib/models/dossier_unifie.dart b/frontend/lib/models/dossier_unifie.dart
index 78b2fb3..0e364fd 100644
--- a/frontend/lib/models/dossier_unifie.dart
+++ b/frontend/lib/models/dossier_unifie.dart
@@ -215,8 +215,13 @@ class EnfantDossier {
   factory EnfantDossier.fromJson(Map<String, dynamic> json) {
     final rawPhoto = json['photo_url'] ?? json['photoUrl'];
     final resolvedPhoto = _optionalPhotoUrl(rawPhoto);
+    final rawId = json['id'] ??
+        json['enfant_id'] ??
+        json['enfantId'] ??
+        json['child_id'] ??
+        json['childId'];
     return EnfantDossier(
-      id: json['id']?.toString() ?? '',
+      id: rawId?.toString().trim() ?? '',
       firstName: (json['first_name'] ?? json['prenom'])?.toString(),
       lastName: (json['last_name'] ?? json['nom'])?.toString(),
       birthDate: json['birth_date']?.toString(),
diff --git a/frontend/lib/services/user_service.dart b/frontend/lib/services/user_service.dart
index be87d9e..4c078aa 100644
--- a/frontend/lib/services/user_service.dart
+++ b/frontend/lib/services/user_service.dart
@@ -525,17 +525,58 @@ class UserService {
     return enfant.copyWith(parentLinks: enriched);
   }
 
+  /// Mise à jour enfant. Avec [photoBytes] : multipart (champ `photo`), sinon JSON.
   static Future<EnfantAdminModel> updateEnfant({
     required String enfantId,
     required Map<String, dynamic> body,
+    List<int>? photoBytes,
+    String? photoFilename,
   }) async {
-    final response = await http.patch(
-      Uri.parse('${ApiConfig.baseUrl}${ApiConfig.enfants}/$enfantId'),
-      headers: await _headers(),
-      body: jsonEncode(body),
-    );
+    final id = enfantId.trim();
+    if (id.isEmpty) {
+      throw Exception('Identifiant enfant manquant.');
+    }
+    final hasPhoto = photoBytes != null && photoBytes.isNotEmpty;
+    final http.Response response;
+    if (hasPhoto) {
+      final token = await TokenService.getToken();
+      final req = http.MultipartRequest(
+        'PATCH',
+        Uri.parse('${ApiConfig.baseUrl}${ApiConfig.enfants}/$id'),
+      );
+      req.headers['Accept'] = 'application/json';
+      if (token != null) {
+        req.headers['Authorization'] = 'Bearer $token';
+      }
+      body.forEach((key, value) {
+        if (value == null) return;
+        req.fields[key] = value is bool
+            ? (value ? 'true' : 'false')
+            : value.toString();
+      });
+      final name = (photoFilename ?? '').trim();
+      final filename = name.isNotEmpty ? name : 'photo.jpg';
+      req.files.add(
+        http.MultipartFile.fromBytes(
+          'photo',
+          photoBytes,
+          filename: filename,
+          contentType: _imageMediaType(filename, photoBytes),
+        ),
+      );
+      final streamed = await req.send();
+      response = await http.Response.fromStream(streamed);
+    } else {
+      response = await http.patch(
+        Uri.parse('${ApiConfig.baseUrl}${ApiConfig.enfants}/$id'),
+        headers: await _headers(),
+        body: jsonEncode(body),
+      );
+    }
     if (response.statusCode != 200) {
-      throw Exception(_extractErrorMessage(response.body, 'Erreur mise à jour enfant'));
+      throw Exception(
+        _extractErrorMessage(response.body, 'Erreur mise à jour enfant'),
+      );
     }
     final enfant = EnfantAdminModel.fromJson(
       jsonDecode(response.body) as Map<String, dynamic>,
@@ -645,6 +686,57 @@ class UserService {
     return fallback;
   }
 
+  /// Ajout d’un co-parent sur foyer mono-parent (staff, #135).
+  /// `POST /parents/:pivotUserId/co-parent` — succès 201.
+  static Future<Map<String, dynamic>> addCoParent(
+    String pivotUserId, {
+    required Map<String, dynamic> body,
+  }) async {
+    final id = pivotUserId.trim();
+    if (id.isEmpty) {
+      throw Exception('Identifiant du parent pivot manquant.');
+    }
+    final http.Response response;
+    try {
+      response = await http.post(
+        Uri.parse('${ApiConfig.baseUrl}${ApiConfig.parents}/$id/co-parent'),
+        headers: await _headers(),
+        body: jsonEncode(body),
+      );
+    } on http.ClientException {
+      throw Exception(
+        'Connexion au serveur impossible. Vérifiez votre réseau puis réessayez.',
+      );
+    }
+
+    if (response.statusCode == 200 || response.statusCode == 201) {
+      if (response.body.trim().isEmpty) return <String, dynamic>{};
+      try {
+        final decoded = jsonDecode(response.body);
+        if (decoded is Map) {
+          return Map<String, dynamic>.from(decoded);
+        }
+      } catch (_) {}
+      return <String, dynamic>{};
+    }
+
+    final message = _extractErrorMessage(
+      response.body,
+      'Erreur ajout co-parent',
+    );
+    if (response.statusCode == 409) {
+      throw Exception(
+        message.isNotEmpty ? message : 'Conflit : e-mail déjà utilisé.',
+      );
+    }
+    if (response.statusCode == 400) {
+      throw Exception(
+        message.isNotEmpty ? message : 'Données invalides (400).',
+      );
+    }
+    throw Exception(message);
+  }
+
   /// Création dossier famille actif côté staff (#129).
   /// `POST /parents/dossier` — body aligné sur register parent complet.
   /// Succès 201 : dossier actif + `numero_dossier` (mail MDP côté serveur, par parent créé).
diff --git a/frontend/lib/widgets/admin/am_dossier_wizard.dart b/frontend/lib/widgets/admin/am_dossier_wizard.dart
index affb5ea..dd6b0cb 100644
--- a/frontend/lib/widgets/admin/am_dossier_wizard.dart
+++ b/frontend/lib/widgets/admin/am_dossier_wizard.dart
@@ -23,9 +23,9 @@ import 'package:p_tits_pas/widgets/admin/validation_valider_confirm_dialog.dart'
 import 'package:p_tits_pas/widgets/common/auth_network_image.dart';
 import 'package:p_tits_pas/widgets/common/identity_block.dart';
 
-enum AmDossierWizardMode { review, create }
+enum AmDossierWizardMode { review, create, edit }
 
-/// Wizard dossier AM — modes [review] (validation pending) et [create] (staff #156).
+/// Wizard dossier AM — [review] (#107), [create] (#156), [edit] (#135).
 class AmDossierWizard extends StatefulWidget {
   final AmDossierWizardMode mode;
   final DossierAM? dossier;
@@ -74,7 +74,25 @@ class AmDossierWizard extends StatefulWidget {
     );
   }
 
+  factory AmDossierWizard.edit({
+    Key? key,
+    required DossierAM dossier,
+    required VoidCallback onClose,
+    required VoidCallback onSuccess,
+    void Function(int step, int total)? onStepChanged,
+  }) {
+    return AmDossierWizard._(
+      key: key,
+      mode: AmDossierWizardMode.edit,
+      dossier: dossier,
+      onClose: onClose,
+      onSuccess: onSuccess,
+      onStepChanged: onStepChanged,
+    );
+  }
+
   bool get isCreate => mode == AmDossierWizardMode.create;
+  bool get isEdit => mode == AmDossierWizardMode.edit;
 
   /// Hauteur corps modale AM — dérivée de [ValidationFormMetrics] (4 lignes).
   static double get shellBodyHeight =>
@@ -118,9 +136,11 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
   String? _photoFilename;
 
   bool get _isCreate => widget.isCreate;
+  bool get _isEdit => widget.isEdit;
+  bool get _isEditable => _isCreate || _isEdit;
   DossierAM get _dossier => widget.dossier!;
   bool get _isEnAttente =>
-      !_isCreate && _dossier.user.statut == 'en_attente';
+      !_isCreate && !_isEdit && _dossier.user.statut == 'en_attente';
 
   static String _v(String? s) =>
       (s != null && s.trim().isNotEmpty) ? s.trim() : '–';
@@ -151,9 +171,33 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
     _capaciteCtrl = TextEditingController(text: '1');
     _placesCtrl = TextEditingController(text: '1');
     _presentationCtrl = TextEditingController();
+    if (_isEdit) {
+      _prefillFromDossier();
+    }
     WidgetsBinding.instance.addPostFrameCallback((_) => _emitStep());
   }
 
+  void _prefillFromDossier() {
+    final u = _dossier.user;
+    _nomCtrl.text = (u.nom ?? '').trim();
+    _prenomCtrl.text = (u.prenom ?? '').trim();
+    _telCtrl.text = (u.telephone ?? '').trim();
+    _emailCtrl.text = u.email.trim();
+    _adresseCtrl.text = (u.adresse ?? '').trim();
+    _cpCtrl.text = (u.codePostal ?? '').trim();
+    _villeCtrl.text = (u.ville ?? '').trim();
+    _nirCtrl.text = (_dossier.nir ?? '').trim();
+    _dateNaissanceCtrl.text = formatIsoDateFrInput(u.dateNaissance);
+    _lieuNaissanceVilleCtrl.text = (u.lieuNaissanceVille ?? '').trim();
+    final pays = (u.lieuNaissancePays ?? '').trim();
+    _lieuNaissancePaysCtrl.text = pays.isEmpty ? 'France' : pays;
+    _agrementCtrl.text = (_dossier.numeroAgrement ?? '').trim();
+    _dateAgrementCtrl.text = formatIsoDateFrInput(_dossier.dateAgrement);
+    _capaciteCtrl.text = '${_dossier.nbMaxEnfants ?? 1}';
+    _placesCtrl.text = '${_dossier.placesDisponibles ?? 0}';
+    _presentationCtrl.text = (_dossier.presentation ?? '').trim();
+  }
+
   @override
   void dispose() {
     _nomCtrl.dispose();
@@ -373,8 +417,8 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
     return null;
   }
 
-  String? _validateStep1() {
-    if (_photoBytes == null || _photoBytes!.isEmpty) {
+  String? _validateStep1({required bool requirePhoto}) {
+    if (requirePhoto && (_photoBytes == null || _photoBytes!.isEmpty)) {
       return 'Une photo de profil est requise.';
     }
     final birthIso = parseFrDateToIso(_dateNaissanceCtrl.text);
@@ -407,12 +451,12 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
   }
 
   String? _validateCurrentStep() {
-    if (!_isCreate) return null;
+    if (!_isEditable) return null;
     switch (_step) {
       case 0:
         return _validateStep0();
       case 1:
-        return _validateStep1();
+        return _validateStep1(requirePhoto: _isCreate);
       default:
         return null;
     }
@@ -511,7 +555,7 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
       );
       return;
     }
-    final err1 = _validateStep1();
+    final err1 = _validateStep1(requirePhoto: true);
     if (err1 != null) {
       ScaffoldMessenger.of(context).showSnackBar(
         SnackBar(content: Text(err1), backgroundColor: Colors.red.shade700),
@@ -554,6 +598,94 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
     }
   }
 
+  Future<void> _saveEdit() async {
+    if (_submitting || !_isEdit) return;
+    final err0 = _validateStep0();
+    if (err0 != null) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(err0), backgroundColor: Colors.red.shade700),
+      );
+      return;
+    }
+    final err1 = _validateStep1(requirePhoto: false);
+    if (err1 != null) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(content: Text(err1), backgroundColor: Colors.red.shade700),
+      );
+      return;
+    }
+
+    final amId = _dossier.user.id.trim();
+    if (amId.isEmpty) {
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: const Text('Identifiant AM manquant.'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+      return;
+    }
+
+    final ok = await showValidationValiderConfirmDialog(
+      context,
+      body: 'Enregistrer les modifications de la fiche assistante maternelle ?',
+    );
+    if (!mounted || !ok) return;
+
+    final birthIso = parseFrDateToIso(_dateNaissanceCtrl.text);
+    final agrementIso = parseFrDateToIso(_dateAgrementCtrl.text);
+    final capa = int.tryParse(_capaciteCtrl.text.trim());
+    final places = int.tryParse(_placesCtrl.text.trim());
+    final biography = _presentationCtrl.text.trim();
+
+    setState(() => _submitting = true);
+    try {
+      await UserService.updateAmFiche(
+        amUserId: amId,
+        body: {
+          'nom': formatPersonNameCase(_nomCtrl.text),
+          'prenom': formatPersonNameCase(_prenomCtrl.text),
+          'email': normalizeEmailText(_emailCtrl.text),
+          'telephone': normalizePhone(_telCtrl.text),
+          'adresse': _adresseCtrl.text.trim(),
+          'ville': formatPersonNameCase(_villeCtrl.text),
+          'code_postal': _cpCtrl.text.trim(),
+          'approval_number': _agrementCtrl.text.trim(),
+          'nir': nirToRaw(_nirCtrl.text),
+          if (birthIso != null) 'date_naissance': birthIso,
+          'lieu_naissance_ville':
+              formatPersonNameCase(_lieuNaissanceVilleCtrl.text),
+          'lieu_naissance_pays':
+              formatPersonNameCase(_lieuNaissancePaysCtrl.text),
+          if (agrementIso != null) 'agreement_date': agrementIso,
+          if (capa != null) 'max_children': capa,
+          if (places != null) 'places_available': places,
+          'biography': biography,
+        },
+      );
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        const SnackBar(
+          content: Text('Fiche AM enregistrée.'),
+          duration: Duration(seconds: 4),
+        ),
+      );
+      widget.onSuccess();
+    } catch (e) {
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(e is Exception
+              ? e.toString().replaceFirst('Exception: ', '')
+              : 'Erreur'),
+          backgroundColor: Colors.red.shade700,
+        ),
+      );
+    } finally {
+      if (mounted) setState(() => _submitting = false);
+    }
+  }
+
   @override
   Widget build(BuildContext context) {
     if (_showRefusForm) {
@@ -587,7 +719,7 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
   }
 
   Widget _buildStep0() {
-    if (_isCreate) {
+    if (_isEditable) {
       return IdentityBlock.editable(
         title: 'Identité et coordonnées',
         nomController: _nomCtrl,
@@ -620,7 +752,7 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
             .clamp(_photoColumnMinWidth, 360.0);
         if (photoW > maxPhotoW) photoW = maxPhotoW;
 
-        final form = _isCreate
+        final form = _isEditable
             ? _buildCreateProFields()
             : ValidationDetailSection(
                 title: 'Dossier professionnel',
@@ -628,20 +760,25 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
                 rowLayout: _photoProRowLayout,
               );
 
+        final Widget photo;
+        if (_isCreate) {
+          photo = AdminAmPhotoFrame(
+            imageBytes: _photoBytes,
+            onTap: _pickPhoto,
+            onClear: _photoBytes != null ? _clearPhoto : null,
+            emptyLabel: 'Ajouter une photo',
+          );
+        } else if (_isEdit) {
+          // Édition : photo existante en lecture ; remplacement hors scope PATCH fiche.
+          photo = _buildPhotoSectionReview(_dossier.user);
+        } else {
+          photo = _buildPhotoSectionReview(_dossier.user);
+        }
+
         return Row(
           crossAxisAlignment: CrossAxisAlignment.stretch,
           children: [
-            SizedBox(
-              width: photoW,
-              child: _isCreate
-                  ? AdminAmPhotoFrame(
-                      imageBytes: _photoBytes,
-                      onTap: _pickPhoto,
-                      onClear: _photoBytes != null ? _clearPhoto : null,
-                      emptyLabel: 'Ajouter une photo',
-                    )
-                  : _buildPhotoSectionReview(_dossier.user),
-            ),
+            SizedBox(width: photoW, child: photo),
             const SizedBox(width: _photoProGap),
             Expanded(
               child: Align(
@@ -721,7 +858,7 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
   }
 
   Widget _buildStep2() {
-    if (_isCreate) {
+    if (_isEditable) {
       return Column(
         crossAxisAlignment: CrossAxisAlignment.stretch,
         children: [
@@ -832,6 +969,12 @@ class _AmDossierWizardState extends State<AmDossierWizard> {
                   onPressed: _submitting ? null : _createAndValidate,
                   child: Text(_submitting ? 'Envoi...' : 'Créer et valider'),
                 ),
+              ] else if (_isEdit) ...[
+                ElevatedButton(
+                  style: ValidationModalTheme.primaryElevatedStyle,
+                  onPressed: _submitting ? null : _saveEdit,
+                  child: Text(_submitting ? 'Envoi...' : 'Enregistrer'),
+                ),
               ] else if (_isEnAttente) ...[
                 OutlinedButton(
                     onPressed: _submitting ? null : _refuser,
diff --git a/frontend/lib/widgets/admin/dossiers_management_widget.dart b/frontend/lib/widgets/admin/dossiers_management_widget.dart
index 62ec3ab..4cafa2f 100644
--- a/frontend/lib/widgets/admin/dossiers_management_widget.dart
+++ b/frontend/lib/widgets/admin/dossiers_management_widget.dart
@@ -85,6 +85,7 @@ class _DossiersManagementWidgetState extends State<DossiersManagementWidget> {
       context: context,
       builder: (context) => ValidationDossierModal(
         numeroDossier: num,
+        openAsEdit: true,
         onClose: () => Navigator.of(context).pop(),
         onSuccess: () {
           Navigator.of(context).pop();
diff --git a/frontend/lib/widgets/admin/parent_dossier_wizard.dart b/frontend/lib/widgets/admin/parent_dossier_wizard.dart
index 262a8a1..b9c7bf1 100644
--- a/frontend/lib/widgets/admin/parent_dossier_wizard.dart
+++ b/frontend/lib/widgets/admin/parent_dossier_wizard.dart
@@ -22,10 +22,15 @@ import 'package:p_tits_pas/widgets/admin/validation_valider_confirm_dialog.dart'
 import 'package:p_tits_pas/widgets/common/auth_network_image.dart';
 import 'package:p_tits_pas/widgets/common/identity_block.dart';
 
-enum ParentDossierWizardMode { review, create }
+enum ParentDossierWizardMode { review, create, edit }
 
-/// Enfant en cours de saisie (mode création). Contrôleurs propres, à disposer.
+/// Enfant en cours de saisie (création / édition). Contrôleurs propres, à disposer.
 class _CreateChild {
+  /// Id existant en base (mode edit) — null = nouvel enfant → POST.
+  String? existingChildId;
+  String? existingPhotoUrl;
+  /// Statut d’origine (hors à naître) pour ne pas écraser garde/scolarise.
+  String? existingStatus;
   final TextEditingController prenomCtrl = TextEditingController();
   final TextEditingController nomCtrl = TextEditingController();
   final TextEditingController dateCtrl = TextEditingController();
@@ -34,6 +39,8 @@ class _CreateChild {
   Uint8List? photoBytes;
   String? photoFilename;
 
+  bool get hasExistingId => (existingChildId ?? '').trim().isNotEmpty;
+
   void dispose() {
     prenomCtrl.dispose();
     nomCtrl.dispose();
@@ -41,8 +48,7 @@ class _CreateChild {
   }
 }
 
-/// Wizard dossier famille — modes [review] (validation dossier en attente, ticket #107)
-/// et [create] (création dossier famille actif par le staff, ticket #129).
+/// Wizard dossier famille — [review] (#107), [create] (#129), [edit] (#135).
 class ParentDossierWizard extends StatefulWidget {
   final ParentDossierWizardMode mode;
   final DossierFamille? dossier;
@@ -91,7 +97,25 @@ class ParentDossierWizard extends StatefulWidget {
     );
   }
 
+  factory ParentDossierWizard.edit({
+    Key? key,
+    required DossierFamille dossier,
+    required VoidCallback onClose,
+    required VoidCallback onSuccess,
+    void Function(int step, int total)? onStepChanged,
+  }) {
+    return ParentDossierWizard._(
+      key: key,
+      mode: ParentDossierWizardMode.edit,
+      dossier: dossier,
+      onClose: onClose,
+      onSuccess: onSuccess,
+      onStepChanged: onStepChanged,
+    );
+  }
+
   bool get isCreate => mode == ParentDossierWizardMode.create;
+  bool get isEdit => mode == ParentDossierWizardMode.edit;
 
   /// Hauteur corps modale famille — 4 lignes TF + marge pour le bandeau switch.
   static double get shellBodyHeight =>
@@ -141,16 +165,27 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
   final List<_CreateChild> _children = [];
   late final TextEditingController _presentationCtrl;
 
+  /// Nb de parents déjà en base au moment de l’ouverture (mode edit).
+  int _initialParentCount = 0;
+
+  /// Enfants existants retirés en edit → DELETE au save.
+  final List<String> _removedEnfantIds = [];
+
   bool get _isCreate => widget.isCreate;
+  bool get _isEdit => widget.isEdit;
+  bool get _isEditable => _isCreate || _isEdit;
   DossierFamille get _dossier => widget.dossier!;
 
-  bool get _isEnAttente => !_isCreate && _dossier.isEnAttente;
+  bool get _isEnAttente => !_isCreate && !_isEdit && _dossier.isEnAttente;
 
   String? get _firstParentId {
     if (_isCreate) return null;
     return _dossier.parents.isNotEmpty ? _dossier.parents.first.id : null;
   }
 
+  /// Co-parent déjà présent au chargement (edit) — pas un ajout via POST.
+  bool get _hadExistingCoParent => _isEdit && _initialParentCount >= 2;
+
   static String _v(String? s) =>
       (s != null && s.trim().isNotEmpty) ? s.trim() : 'Non défini';
 
@@ -184,11 +219,81 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
     _presentationCtrl = TextEditingController();
     if (_isCreate) {
       _children.add(_CreateChild());
+    } else if (_isEdit) {
+      _prefillFromDossier();
     }
 
     WidgetsBinding.instance.addPostFrameCallback((_) => _emitStep());
   }
 
+  void _prefillFromDossier() {
+    final parents = _dossier.parents;
+    _initialParentCount = parents.length;
+
+    if (parents.isNotEmpty) {
+      final p1 = parents.first;
+      _p1NomCtrl.text = (p1.nom ?? '').trim();
+      _p1PrenomCtrl.text = (p1.prenom ?? '').trim();
+      _p1TelCtrl.text = (p1.telephone ?? '').trim();
+      _p1EmailCtrl.text = (p1.email).trim();
+      _p1AdresseCtrl.text = (p1.adresse ?? '').trim();
+      _p1CpCtrl.text = (p1.codePostal ?? '').trim();
+      _p1VilleCtrl.text = (p1.ville ?? '').trim();
+
+      if (parents.length >= 2) {
+        _hasCoParent = true;
+        final p2 = parents[1];
+        _p2NomCtrl.text = (p2.nom ?? '').trim();
+        _p2PrenomCtrl.text = (p2.prenom ?? '').trim();
+        _p2TelCtrl.text = (p2.telephone ?? '').trim();
+        _p2EmailCtrl.text = (p2.email).trim();
+        _p2AdresseCtrl.text = (p2.adresse ?? '').trim();
+        _p2CpCtrl.text = (p2.codePostal ?? '').trim();
+        _p2VilleCtrl.text = (p2.ville ?? '').trim();
+      } else {
+        _hasCoParent = false;
+      }
+    }
+
+    _prefillChildrenFromDossier();
+  }
+
+  void _prefillChildrenFromDossier() {
+    for (final c in _children) {
+      c.dispose();
+    }
+    _children.clear();
+    _removedEnfantIds.clear();
+
+    final enfants = _dossier.enfants;
+    if (enfants.isEmpty) {
+      _children.add(_CreateChild());
+      return;
+    }
+
+    for (final e in enfants) {
+      final status = (e.status ?? '').trim().toLowerCase();
+      final id = e.id.trim();
+      final child = _CreateChild()
+        ..existingChildId = id.isEmpty ? null : id
+        ..existingPhotoUrl = e.photoUrl
+        ..existingStatus = status.isEmpty ? null : status
+        ..isUnborn = status == 'a_naitre';
+      child.prenomCtrl.text = (e.firstName ?? '').trim();
+      child.nomCtrl.text = (e.lastName ?? '').trim();
+      final g = (e.gender ?? '').trim();
+      final gUp = g.toUpperCase();
+      if (gUp == 'H' || gUp == 'F') {
+        child.genre = gUp;
+      } else if (g == 'Autre' || child.isUnborn) {
+        child.genre = child.isUnborn ? 'Autre' : g;
+      }
+      final dateSrc = child.isUnborn ? e.dueDate : e.birthDate;
+      child.dateCtrl.text = formatIsoDateFrInput(dateSrc);
+      _children.add(child);
+    }
+  }
+
   @override
   void dispose() {
     _enfantsScrollController.removeListener(_syncEnfantsScrollFades);
@@ -291,7 +396,7 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
   }
 
   Widget _buildStep0() {
-    if (_isCreate) {
+    if (_isEditable) {
       return IdentityBlock.editable(
         title: 'Parent principal',
         nomController: _p1NomCtrl,
@@ -310,13 +415,15 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
   }
 
   Widget _buildStep1() {
-    if (_isCreate) {
-      return _buildCoParentStepCreate();
+    if (_isEditable) {
+      return _buildCoParentStepEditable(
+        allowToggle: !_hadExistingCoParent,
+      );
     }
     return _buildParent2Step();
   }
 
-  Widget _buildCoParentStepCreate() {
+  Widget _buildCoParentStepEditable({required bool allowToggle}) {
     return Column(
       crossAxisAlignment: CrossAxisAlignment.stretch,
       children: [
@@ -330,19 +437,21 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
                 color: Colors.black87,
               ),
             ),
-            const Spacer(),
-            const Text(
-              'Ajouter un co-parent',
-              style: TextStyle(fontSize: 14, color: Colors.black87),
-            ),
-            Transform.scale(
-              scale: 0.75,
-              child: Switch(
-                materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
-                value: _hasCoParent,
-                onChanged: (v) => setState(() => _hasCoParent = v),
+            if (allowToggle) ...[
+              const Spacer(),
+              const Text(
+                'Ajouter un co-parent',
+                style: TextStyle(fontSize: 14, color: Colors.black87),
               ),
-            ),
+              Transform.scale(
+                scale: 0.75,
+                child: Switch(
+                  materialTapTargetSize: MaterialTapTargetSize.shrinkWrap,
+                  value: _hasCoParent,
+                  onChanged: (v) => setState(() => _hasCoParent = v),
+                ),
+              ),
+            ],
           ],
         ),
         const SizedBox(height: 8),
@@ -539,7 +648,7 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
   }
 
   Widget _buildEnfantsStep() {
-    if (_isCreate) {
+    if (_isCreate || _isEdit) {
       return _buildEnfantsStepCreate();
     }
     final enfants = _dossier.enfants;
@@ -618,6 +727,10 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
     if (_children.length <= 1) return;
     setState(() {
       final removed = _children.removeAt(index);
+      final existingId = (removed.existingChildId ?? '').trim();
+      if (existingId.isNotEmpty) {
+        _removedEnfantIds.add(existingId);
+      }
       removed.dispose();
     });
   }
@@ -706,7 +819,8 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
               crossAxisAlignment: CrossAxisAlignment.stretch,
               children: [
                 Padding(
-                  padding: const EdgeInsets.fromLTRB(12, 12, 14, 8),
+                  // Réserve l’angle haut-droit pour la croix de suppression.
+                  padding: EdgeInsets.fromLTRB(12, 12, canRemove ? 36 : 14, 8),
                   child: ValidationLabeledField(
                     label: 'Prénom',
                     field: ValidationEditableField(
@@ -747,6 +861,9 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
                                   width: pw,
                                   height: ph,
                                   child: AdminAmPhotoFrame(
+                                    photoUrl: child.photoBytes == null
+                                        ? child.existingPhotoUrl
+                                        : null,
                                     imageBytes: child.photoBytes,
                                     onTap: () => _pickChildPhoto(index),
                                     onClear: child.photoBytes != null
@@ -833,19 +950,28 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
             ),
             if (canRemove)
               Positioned(
-                top: 4,
-                right: 4,
+                top: 6,
+                right: 6,
                 child: Material(
-                  color: Colors.transparent,
-                  child: IconButton(
-                    tooltip: 'Retirer cet enfant',
-                    visualDensity: VisualDensity.compact,
-                    padding: EdgeInsets.zero,
-                    constraints:
-                        const BoxConstraints(minWidth: 32, minHeight: 32),
-                    icon: Icon(Icons.close,
-                        size: 18, color: Colors.grey.shade700),
-                    onPressed: () => _removeChild(index),
+                  color: Colors.white,
+                  elevation: 1,
+                  shape: const CircleBorder(),
+                  clipBehavior: Clip.antiAlias,
+                  child: InkWell(
+                    customBorder: const CircleBorder(),
+                    onTap: () => _removeChild(index),
+                    child: Tooltip(
+                      message: 'Retirer cet enfant',
+                      child: SizedBox(
+                        width: 22,
+                        height: 22,
+                        child: Icon(
+                          Icons.close,
+                          size: 14,
+                          color: Colors.grey.shade800,
+                        ),
+                      ),
+                    ),
                   ),
                 ),
               ),
@@ -1264,6 +1390,18 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
   }
 
   String? _validateCurrentStep() {
+    if (_isEdit) {
+      switch (_step) {
+        case 0:
+          return _validateP1();
+        case 1:
+          return _validateP2();
+        case 2:
+          return _validateEnfants();
+        default:
+          return null;
+      }
+    }
     if (!_isCreate) return null;
     switch (_step) {
       case 0:
@@ -1440,6 +1578,299 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
     }
   }
 
+  Map<String, dynamic> _parentFicheBody({
+    required TextEditingController nom,
+    required TextEditingController prenom,
+    required TextEditingController email,
+    required TextEditingController tel,
+    required TextEditingController adresse,
+    required TextEditingController cp,
+    required TextEditingController ville,
+  }) {
+    return {
+      'nom': formatPersonNameCase(nom.text),
+      'prenom': formatPersonNameCase(prenom.text),
+      'email': normalizeEmailText(email.text),
+      'telephone': normalizePhone(tel.text),
+      'adresse': adresse.text.trim(),
+      'ville': formatPersonNameCase(ville.text),
+      'code_postal': cp.text.trim(),
+    };
+  }
+
+  Future<void> _saveEdit() async {
+    if (_submitting || !_isEdit) return;
+    final err0 = _validateP1();
+    if (err0 != null) {
+      _showError(err0);
+      return;
+    }
+    final err1 = _validateP2();
+    if (err1 != null) {
+      _showError(err1);
+      return;
+    }
+    final err2 = _validateEnfants();
+    if (err2 != null) {
+      _showError(err2);
+      return;
+    }
+
+    final pivotId = (_firstParentId ?? '').trim();
+    if (pivotId.isEmpty) {
+      _showError('Identifiant du parent principal manquant.');
+      return;
+    }
+
+    final addingCoParent = _hasCoParent && !_hadExistingCoParent;
+    final ok = await showValidationValiderConfirmDialog(
+      context,
+      body: addingCoParent
+          ? 'Enregistrer le dossier et ajouter le co-parent ? Un e-mail de création de mot de passe lui sera envoyé.'
+          : 'Enregistrer les modifications du dossier famille ?',
+    );
+    if (!mounted || !ok) return;
+
+    setState(() => _submitting = true);
+    try {
+      await UserService.updateParentFiche(
+        parentUserId: pivotId,
+        body: _parentFicheBody(
+          nom: _p1NomCtrl,
+          prenom: _p1PrenomCtrl,
+          email: _p1EmailCtrl,
+          tel: _p1TelCtrl,
+          adresse: _p1AdresseCtrl,
+          cp: _p1CpCtrl,
+          ville: _p1VilleCtrl,
+        ),
+      );
+
+      if (_hadExistingCoParent) {
+        final coId = _dossier.parents[1].id.trim();
+        if (coId.isEmpty) {
+          throw Exception('Identifiant du co-parent manquant.');
+        }
+        await UserService.updateParentFiche(
+          parentUserId: coId,
+          body: _parentFicheBody(
+            nom: _p2NomCtrl,
+            prenom: _p2PrenomCtrl,
+            email: _p2EmailCtrl,
+            tel: _p2TelCtrl,
+            adresse: _p2AdresseCtrl,
+            cp: _p2CpCtrl,
+            ville: _p2VilleCtrl,
+          ),
+        );
+      } else if (addingCoParent) {
+        if (_sameAddress) _copyP1AddressToP2();
+        final body = <String, dynamic>{
+          'email': normalizeEmailText(_p2EmailCtrl.text),
+          'prenom': formatPersonNameCase(_p2PrenomCtrl.text),
+          'nom': formatPersonNameCase(_p2NomCtrl.text),
+          'telephone': normalizePhone(_p2TelCtrl.text),
+          'meme_adresse': _sameAddress,
+        };
+        if (!_sameAddress) {
+          body['adresse'] = _p2AdresseCtrl.text.trim();
+          body['code_postal'] = _p2CpCtrl.text.trim();
+          body['ville'] = formatPersonNameCase(_p2VilleCtrl.text);
+        }
+        await UserService.addCoParent(pivotId, body: body);
+      }
+
+      await _saveEnfantsEdit(pivotId);
+
+      if (!mounted) return;
+      ScaffoldMessenger.of(context).showSnackBar(
+        SnackBar(
+          content: Text(
+            addingCoParent
+                ? 'Dossier enregistré. Co-parent ajouté.'
+                : 'Dossier enregistré.',
+          ),
+          duration: const Duration(seconds: 4),
+        ),
+      );
+      widget.onSuccess();
+    } catch (e) {
+      if (!mounted) return;
+      _showError(
+        e is Exception ? e.toString().replaceFirst('Exception: ', '') : 'Erreur',
+      );
+    } finally {
+      if (mounted) setState(() => _submitting = false);
+    }
+  }
+
+  Map<String, dynamic> _enfantStaffBody(_CreateChild c) {
+    final prenom = formatPersonNameCase(c.prenomCtrl.text);
+    final nomRaw = c.nomCtrl.text.trim();
+    final nom = nomRaw.isNotEmpty
+        ? formatPersonNameCase(nomRaw)
+        : formatPersonNameCase(_p1NomCtrl.text);
+    final dateIso = parseFrDateToIso(c.dateCtrl.text);
+    final existingStatus = (c.existingStatus ?? '').trim().toLowerCase();
+    final status = c.isUnborn
+        ? 'a_naitre'
+        : (existingStatus.isNotEmpty && existingStatus != 'a_naitre'
+            ? existingStatus
+            : 'sans_garde');
+    final gender = c.genre ?? 'H';
+
+    final map = <String, dynamic>{
+      'status': status,
+      'gender': gender,
+      'consent_photo': true,
+      'is_multiple': false,
+    };
+    if (prenom.length >= 2) map['first_name'] = prenom;
+    if (nom.length >= 2) map['last_name'] = nom;
+    if (c.isUnborn) {
+      if (dateIso != null) map['due_date'] = dateIso;
+    } else if (dateIso != null) {
+      map['birth_date'] = dateIso;
+    }
+    return map;
+  }
+
+  /// Empreinte identité pour rattacher un brouillon sans id à un enfant du GET.
+  String _enfantIdentityKey({
+    required String prenom,
+    required String nom,
+    required String? dateIso,
+    required bool isUnborn,
+  }) {
+    final pn = formatPersonNameCase(prenom).toLowerCase().trim();
+    final nm = formatPersonNameCase(nom).toLowerCase().trim();
+    final d = _normalizeDateKey(dateIso);
+    final kind = isUnborn ? 'due' : 'birth';
+    return '$pn|$nm|$kind|$d';
+  }
+
+  String _normalizeDateKey(String? raw) {
+    final s = (raw ?? '').trim();
+    if (s.isEmpty) return '';
+    final fromFr = parseFrDateToIso(s);
+    if (fromFr != null) return fromFr;
+    try {
+      final dt = DateTime.parse(s);
+      final y = dt.year.toString().padLeft(4, '0');
+      final m = dt.month.toString().padLeft(2, '0');
+      final d = dt.day.toString().padLeft(2, '0');
+      return '$y-$m-$d';
+    } catch (_) {
+      return s;
+    }
+  }
+
+  String _enfantKeyFromCreate(_CreateChild c) {
+    final prenom = formatPersonNameCase(c.prenomCtrl.text);
+    final nomRaw = c.nomCtrl.text.trim();
+    final nom = nomRaw.isNotEmpty
+        ? formatPersonNameCase(nomRaw)
+        : formatPersonNameCase(_p1NomCtrl.text);
+    return _enfantIdentityKey(
+      prenom: prenom,
+      nom: nom,
+      dateIso: parseFrDateToIso(c.dateCtrl.text),
+      isUnborn: c.isUnborn,
+    );
+  }
+
+  String _enfantKeyFromDossier(EnfantDossier e) {
+    final isUnborn = (e.status ?? '').trim().toLowerCase() == 'a_naitre';
+    final nomRaw = (e.lastName ?? '').trim();
+    final nom = nomRaw.isNotEmpty ? nomRaw : (_p1NomCtrl.text.trim());
+    return _enfantIdentityKey(
+      prenom: e.firstName ?? '',
+      nom: nom,
+      dateIso: isUnborn ? e.dueDate : e.birthDate,
+      isUnborn: isUnborn,
+    );
+  }
+
+  bool _isBlankChildDraft(_CreateChild c) {
+    if (c.hasExistingId) return false;
+    final prenom = c.prenomCtrl.text.trim();
+    final nom = c.nomCtrl.text.trim();
+    final date = c.dateCtrl.text.trim();
+    return prenom.isEmpty && nom.isEmpty && date.isEmpty && c.genre == null;
+  }
+
+  /// Résout l’id enfant : tracker edit, sinon match sur le GET dossier.
+  String? _resolveExistingChildId(
+    _CreateChild c,
+    Map<String, String> dossierIdByIdentity,
+    Set<String> alreadyUsedIds,
+  ) {
+    final tracked = (c.existingChildId ?? '').trim();
+    if (tracked.isNotEmpty && !alreadyUsedIds.contains(tracked)) {
+      return tracked;
+    }
+    final key = _enfantKeyFromCreate(c);
+    final matched = (dossierIdByIdentity[key] ?? '').trim();
+    if (matched.isNotEmpty && !alreadyUsedIds.contains(matched)) {
+      return matched;
+    }
+    return null;
+  }
+
+  Future<void> _saveEnfantsEdit(String pivotUserId) async {
+    // Index id connus du GET (ne jamais POST pour ceux-là).
+    final dossierIdByIdentity = <String, String>{};
+    for (final e in _dossier.enfants) {
+      final id = e.id.trim();
+      if (id.isEmpty) continue;
+      dossierIdByIdentity[_enfantKeyFromDossier(e)] = id;
+    }
+
+    for (final id in _removedEnfantIds) {
+      await UserService.deleteEnfant(id);
+    }
+
+    final usedIds = <String>{..._removedEnfantIds};
+    for (final c in _children) {
+      if (_isBlankChildDraft(c)) continue;
+
+      final existingId = _resolveExistingChildId(
+        c,
+        dossierIdByIdentity,
+        usedIds,
+      );
+      final body = _enfantStaffBody(c);
+
+      if (existingId != null && existingId.isNotEmpty) {
+        // Ré-attache l’id au modèle (si match identité a récupéré un id perdu).
+        c.existingChildId = existingId;
+        final bytes = c.photoBytes;
+        await UserService.updateEnfant(
+          enfantId: existingId,
+          body: body,
+          photoBytes: (bytes != null && bytes.isNotEmpty) ? bytes : null,
+          photoFilename: c.photoFilename,
+        );
+        usedIds.add(existingId);
+        continue;
+      }
+
+      // Uniquement les vrais nouveaux enfants (pas d’id dossier).
+      final bytes = c.photoBytes;
+      final created = await UserService.createEnfant(
+        parentUserId: pivotUserId,
+        body: body,
+        photoBytes: (bytes != null && bytes.isNotEmpty) ? bytes : null,
+        photoFilename: c.photoFilename,
+      );
+      final newId = created.id.trim();
+      if (newId.isNotEmpty) {
+        c.existingChildId = newId;
+        usedIds.add(newId);
+      }
+    }
+  }
+
   Widget _buildNavigation() {
     if (_step == 3) {
       return Row(
@@ -1463,6 +1894,12 @@ class _ParentDossierWizardState extends State<ParentDossierWizard> {
                   onPressed: _submitting ? null : _createAndValidate,
                   child: Text(_submitting ? 'Envoi...' : 'Créer et valider'),
                 ),
+              ] else if (_isEdit) ...[
+                ElevatedButton(
+                  style: ValidationModalTheme.primaryElevatedStyle,
+                  onPressed: _submitting ? null : _saveEdit,
+                  child: Text(_submitting ? 'Envoi...' : 'Enregistrer'),
+                ),
               ] else if (_isEnAttente && _firstParentId != null) ...[
                 OutlinedButton(
                     onPressed: _submitting ? null : _refuser,
diff --git a/frontend/lib/widgets/admin/validation_dossier_modal.dart b/frontend/lib/widgets/admin/validation_dossier_modal.dart
index 7bc3faf..fefac12 100644
--- a/frontend/lib/widgets/admin/validation_dossier_modal.dart
+++ b/frontend/lib/widgets/admin/validation_dossier_modal.dart
@@ -2,20 +2,25 @@ import 'package:flutter/material.dart';
 import 'package:p_tits_pas/models/dossier_unifie.dart';
 import 'package:p_tits_pas/services/user_service.dart';
 import 'package:p_tits_pas/widgets/admin/am_dossier_wizard.dart';
+import 'package:p_tits_pas/widgets/admin/parent_dossier_wizard.dart';
 import 'package:p_tits_pas/widgets/admin/validation_am_wizard.dart';
 import 'package:p_tits_pas/widgets/admin/validation_family_wizard.dart';
 
-/// Modale (dialog) : charge le dossier par numéro puis affiche le wizard AM ou Famille. Ticket #107, #119.
+/// Modale (dialog) : charge le dossier par numéro puis affiche le wizard AM ou Famille.
+/// Ticket #107 / #119 (review), #135 (`openAsEdit`).
 class ValidationDossierModal extends StatefulWidget {
   final String numeroDossier;
   final VoidCallback onClose;
   final VoidCallback? onSuccess;
+  /// Liste Dossiers actifs → mode edit (#135). Pending reste en review (défaut).
+  final bool openAsEdit;
 
   const ValidationDossierModal({
     super.key,
     required this.numeroDossier,
     required this.onClose,
     this.onSuccess,
+    this.openAsEdit = false,
   });
 
   @override
@@ -77,12 +82,12 @@ class _ValidationDossierModalState extends State<ValidationDossierModal> {
 
   /// Largeur modale = 1,5 × 620.
   static const double _modalWidth = 930; // 620 * 1.5
-  static const double _familyBodyHeight = 435;
 
   double get _bodyHeight {
     final d = _dossier;
     if (d != null && d.isAm) return AmDossierWizard.shellBodyHeight;
-    return _familyBodyHeight;
+    // Aligné create (#129) / edit (#135) — évite overflow IdentityBlock (8px).
+    return ParentDossierWizard.shellBodyHeight;
   }
 
   @override
@@ -162,6 +167,14 @@ class _ValidationDossierModalState extends State<ValidationDossierModal> {
     }
     final d = _dossier!;
     if (d.isAm) {
+      if (widget.openAsEdit) {
+        return AmDossierWizard.edit(
+          dossier: d.asAm,
+          onClose: widget.onClose,
+          onSuccess: _onSuccess,
+          onStepChanged: _onStepChanged,
+        );
+      }
       return ValidationAmWizard(
         dossier: d.asAm,
         onClose: widget.onClose,
@@ -169,6 +182,14 @@ class _ValidationDossierModalState extends State<ValidationDossierModal> {
         onStepChanged: _onStepChanged,
       );
     }
+    if (widget.openAsEdit) {
+      return ParentDossierWizard.edit(
+        dossier: d.asFamily,
+        onClose: widget.onClose,
+        onSuccess: _onSuccess,
+        onStepChanged: _onStepChanged,
+      );
+    }
     return ValidationFamilyWizard(
       dossier: d.asFamily,
       onClose: widget.onClose,