Does a husband's support for his wife's vow to slaughter a sheep upon the completion of her pregnancy constitute a vow upon him?

If the wife vowed to slaughter a sheep upon the completion of her pregnancy and the husband approved her vow, then she must fulfill it upon the completion of the pregnancy, based on the words of Allah Almighty: {And let them fulfill their vows}, and the words of the Prophet, peace and blessings be upon him: "Whoever vows to obey Allah, let him obey Him." As for the husband's approval, it is not considered a vow binding upon him.

However, if the wife vowed that the husband should slaughter a sheep upon the completion of the pregnancy, then nothing is incumbent upon her; because she vowed something she does not have the power to execute, based on the words of the Prophet, peace and blessings be upon him: "There is no vow in disobedience, nor in what the servant does not possess." As for the husband, if he uttered a form of words indicating commitment, then he is obliged to fulfill his vow; otherwise, nothing is incumbent upon him.