Is it permissible to give zakat to the needy children of a deceased sister whose father had given them money to invest?

Zakat (definition) is paid to the eight categories. If the father's grandchildren are wealthy, zakat is not to be paid to them, even if the money is invested for them. If their poverty is established and their father is unable to provide for them, then their maintenance becomes obligatory upon their grandfather (their mother's father) according to the majority of jurists. If the grandfather does not provide for them and they do not find another provider, it is permissible to pay zakat to them because their maintenance is not obligatory upon you.