Is it permissible for a father or mother to pay their Zakat to their needy daughter and her husband, and is it a condition to inform the husband that it is Zakat?

It is permissible for a father or mother to give their poor daughter from Zakat if her maintenance is not obligatory upon them. It is not a condition to inform her husband of this; rather, it is better to conceal the matter, because Zakat is a charity, and concealing charity is closer to sincerity, in fulfillment of the Almighty's saying: "If you disclose your charities, it is well; but if you conceal them and give them to the poor, it is better for you, and He will remove from you some of your evil deeds. And Allah is Acquainted with what you do." And in accordance with the Prophet's (peace and blessings be upon him) saying regarding the seven whom Allah will shade: "... and a man who gave in charity and hid it such that his left hand did not know what his right hand spent."