Is the person who possesses a document proving he is the son of the deceased considered their sole legal heir, if others are unable to prove their lineage?

The judge or estate distributor must ensure that all heirs are accounted for before division. If the estate is divided and a new heir emerges, he must prove his claim with legitimate evidence. At that point, the division is revoked, and he is given his share. Al-Hattab said: "If an heir appears and the divided property is a house, he has the right to annul the division. If the divided property is a specific item, he can reclaim it from them." The division is also annulled if an error occurs in it, or if a will or debt comes to light.