Is the aforementioned division of the building among the brothers and sisters, which was carried out by virtue of agreements and contracts, in accordance with Islamic law, knowing that the parties' father is still alive?

If a son builds on his father's land with the father's consent, then the building belongs to the son and the land belongs to the father. It is permissible to agree that the son gives his siblings apartments from what he built in exchange for his share in the land. This issue involves two gifts from the father: one to the building son and one to his siblings. In both cases, justice must be observed among the children, male and female. If the father singles out one or prefers one over another, he has committed a sin, and equalization becomes obligatory, either by returning the excess or by completing the share of the other. Care should be taken to maintain kinship ties and equality in rights, and what the brother spent should be returned to him.