Is it permissible for a sick husband who prays sitting and is prone to much forgetfulness in his prayer to pray behind his wife as a follower to reduce his forgetfulness, and what is the best way for him to pray so that his prayer is valid?

The correct view, held by the majority of jurists, is that it is not valid for a man to be led in prayer by a woman, whether he is ill or healthy. This is because a woman is not qualified to lead men, and it is impermissible for her to be an imam for a man in prayer under any circumstances. As for a man's frequent forgetfulness, he should perform what he believes is the correct number of prayers and not pay attention to doubt. He is not required to perform the prostration of forgetfulness (sujud (definition) al-sahw).