Is it permissible to give zakat on wealth to a grandson who is about to get married?

A wealthy individual must spend on their poor ascendants and descendants, and it is not permissible for them to give them Zakat to absolve themselves of an obligation. Ascendants are fathers, mothers, grandfathers, and grandmothers, while descendants are sons, daughters, and grandchildren. However, if the Zakat-payer is not obligated to spend on his daughter's son due to insufficient wealth, it is permissible for him to give him Zakat.