Is it permissible for a mother to be appointed as an agent to fulfill a vow on behalf of her daughter if the daughter is unable to fulfill the vow herself?

This type of vow is called a conditional vow, and it is disliked (makrooh). However, it is obligatory to fulfill it when the desired condition upon which it was made is met, based on Allah's saying: "And let them fulfill their vows," and the Prophet's (peace be upon him) saying: "Whoever vows to obey Allah, let him obey Him." If it was not stipulated that the person making the vow must personally go out to give the charity, then it is permissible for him to appoint his mother or someone else to carry it out.