To what extent is it lawful and obligatory to activate the waqf of the deceased woman that deprived the remaining heirs of their inheritance?

What your aunt has endowed for her nephews and nieces falls into three categories:

1. She endowed it during her health as an immediate endowment (waqf munajaz): The endowment is valid and enforceable according to her condition. 2. She endowed it during her health, conditioned upon her death. 3. She endowed it during her death illness (marad al-mawt).

In the second and third cases, the endowment is considered a will (wasiyah) and is not valid for more than one-third of the estate unless the heirs approve. If they do not approve, they are entitled to two-thirds of the inheritance, and one-third of the endowment from her estate proceeds. An endowment made during a death illness or conditioned upon death is considered akin to a will, and it is calculated from one-third of the wealth, similar to manumission (itq) and gifts (hibah), unless the heirs permit the excess.