Is it valid for a man to perform Hajj on behalf of a woman, or for a woman to perform it on behalf of a man?

Question:
May Allah reward you. What is the ruling on a man performing Hajj on behalf of a woman, or the reverse, and is it sufficient?

Answer:
Yes, it is permissible for a woman to perform Hajj on behalf of a man, because a woman asked the Prophet (peace and blessings be upon him) about her father, who had reached the age where the obligation of Hajj became due for him, but he was unable to stay mounted on his mount due to old age. He said to her, "Perform Hajj on behalf of your father." A woman may perform Hajj on behalf of a man, and a man may also perform Hajj on behalf of a woman; there is no objection to that. Yes.