Is it permissible for a grandmother to give her Zakat money to her daughter, who lives with her and consumes from this money, knowing that the daughter spends it on the household?

It is not permissible to give Zakat except to the eight categories mentioned in the Qur’an. It is not permissible for a father to pay his Zakat to his son if the son's maintenance is obligatory upon him due to his young age or inability, nor is it permissible to give it to a child who is able to earn a living or is wealthy. It is also not permissible to pay Zakat to a poor woman whose husband is rich and provides for her. An exception to this is if she is in debt, in which case she can be given from the share of those in debt (al-Gharimin). If she is in need of maintenance and is not sufficiently provided for by her husband or children, then it is permissible for the mother to pay Zakat to her. However, she (the mother) should not reside with her (the daughter) and eat from her (the daughter's) maintenance.