To what extent is it lawful for a young man to own his aunt's land, which she registered in his name, with a will to use its proceeds for charitable work after her death? Do his maternal uncles have the right to claim their sister's inheritance after her death? And what if he dies before his aunt?

It is not permissible for a donor to intend, by their gift or bequest, to disinherit some heirs. This is among the forbidden acts, indeed, among the grave sins, for Ibn Abbas, may Allah be pleased with them both, said: "Causing harm through a will is among the grave sins." And whoever makes a fictitious sale to disinherit heirs has committed injustice and transgressed the bounds of Allah. Allah Almighty has divided inheritance justly, as He says: "For men is a share of what the parents and close relatives leave, and for women is a share of what the parents and close relatives leave, be it little or much – a prescribed share."