diff --git a/reasoning_gym/graphs/family_relationships.py b/reasoning_gym/graphs/family_relationships.py
index 828f538e..155242a6 100644
--- a/reasoning_gym/graphs/family_relationships.py
+++ b/reasoning_gym/graphs/family_relationships.py
@@ -272,15 +272,18 @@ class FamilyRelationshipsDataset(ProceduralDataset):
         
         family.update([father, mother, uncle, aunt_by_marriage, aunt, uncle_by_marriage])
 
-        # Add children
+        # Add children, randomly assigned to couples
+        couples = [(father, mother), (uncle, aunt_by_marriage), (aunt, uncle_by_marriage)]
         while len(family) < family_size:
             gender = rng.choice([Gender.MALE, Gender.FEMALE])
             name = get_name(gender)
             if not name:
                 break
             child = Person(name, gender, next(id_counter))
-            father.add_child(child)
-            mother.add_child(child)
+            # Randomly choose parents for this child
+            parents = rng.choice(couples)
+            parents[0].add_child(child)  # Add to father/uncle/aunt
+            parents[1].add_child(child)  # Add to mother/aunt_by_marriage/uncle_by_marriage
             family.add(child)
 
         return family