Am I entitled to reclaim my inheritance rights, which I relinquished to my deceased brother for his care and benefit, and what must I do?

If a sister grants her share of an inheritance to her brother and he takes possession of it, she is not permitted to retract the gift, and upon his death, the gift transfers to his heirs. If she intended that she relinquished her right for the duration of her brother's life, to return to her after his death (a life estate or 'umra), the ruling, according to the preponderant opinion, does not differ; for a life estate ('umra) is a transfer of ownership of both the substance and the usufruct, and it transfers to the heirs of the grantee upon his death.