Chapter: It is permissible for a menstruating woman to wash her husband’s head, and comb his hair; her leftovers are pure (tahir); and regarding reclining in her lap and reciting Qur’an

It is reported from 'A'isha that she observed: When the Messenger of Allah (ﷺ) was in I'tikaf, he inclined his head towards me and I combedhis hair, and he did not enter the house but for the natural calls (for relieving himself).