Is the paternal half-brother who sold his share of the inheritance, mismanaged the money, and cut ties with his parents, entitled to claim inheritance, and is the father sinful for disinheriting him and transferring his assets to the mother?

An agreement to waive inheritance before the death of the inheritor is void. Therefore, the brother's right to inheritance is established, and the money he took in exchange for the waiver must be returned, or a set-off can occur between the amount and his share of the inheritance. What the father did by registering his properties in his wife's name is not permissible, and all his estate must be divided among the heirs according to their legal shares. If there is no consent to give the brother his share, the case can be referred to the Sharia (definition) court.