What is the ruling on changing lineage in official documents? Is it permissible for an uncle to bequeath all his money to his adopted son? What is the share of the full brother from the father in the inheritance? And is it permissible for the siblings to gift the entire inheritance to the adopted son?

Adoption is forbidden (haram). The nephew must nullify this adoption and change his name and lineage to that of his real father, as he has no right to inherit (from the adoptive father). Furthermore, the nephew does not inherit from his paternal uncle if there are full siblings who disinherit him completely. It is permissible for the uncle to bequeath up to one-third of his wealth or less to his nephew. More than one-third is not permissible without the consent of the heirs. It is permissible for the uncle's siblings to gift their share of the inheritance to their nephew, provided they are adult, sane, and of sound judgment.