If you gave her the inheritance as a gift, it becomes hers!

However, she must not give a gift to one of her children while depriving the others!

After my father’s death we siblings being the only inheritors alive and my mother,We gave the custody of inheritance to mother stating we have no objection in her taking over the inheritance, we signed the documents in front of the judge making her the rightful owner of the inheritance .So she can do anything like buy a flat for my brother from that money which will be his only? please explain