Is it permissible to give food to the a mother without the knowledge of her daughter's husband, who swore an oath to prevent her from entering the house?

The father should be advised not to prevent his wife's mother from entering his house, and he should expiate his oath to avoid discord. He must commit to not allowing her into his house except with his permission. As for giving her food, it is permissible if it is from the questioner's own money. However, if it is from the father's money, it is not permissible except with his permission, except for what the Prophet, peace and blessings be upon him, permitted for a woman to spend on herself and her child in a reasonable manner.