What is the ruling on a mother’s bequest to her daughter of money she deposited in the daughter’s name for the care of her deceased brother’s children? Is the daughter permitted to dispose of it and invest it? What is the ruling on the money generated from this investment? How can she return this money to her siblings without severing ties of kinship? Is she permitted to pay zakat on the invested money without her siblings’ knowledge?

A mother's bequest of money to her grandchildren is considered a bequest to a non-heir, and it is valid and enforceable only within the limit of one-third of the estate. Any amount exceeding one-third depends on the consent of the heirs, based on the Prophet Muhammad's (peace be upon him) saying: "One-third, and one-third is much." If the bequeathed amount is equal to or less than one-third, it is enforceable and disbursed to the beneficiaries. The heirs must be informed of this to assess whether the amount exceeds one-third. The guardian may invest the orphan's money for his benefit, and all profits belong to the orphan. Zakat is obligatory on the child's wealth if it reaches the nisab (minimum threshold) and a full year has passed, and the guardian must pay it, based on his (peace be upon him) saying: "Whoever takes charge of an orphan who has wealth, let him trade with it for him, and not leave it until sadaqah (charity/zakat) consumes it." The ownership apartment left by the mother is included in the inheritance for the purpose of estimating the one-third, and the grandchildren have no right to it except through the heirs' donation.