Is it permissible for the wife to give the Zakah (obligatory charity) of her money to her poor husband?
Yes, it is permissible for the wife to give from the Zakah of her money to her poor husband. And Allah Knows Best.
Should missed Sunnah prayer be made up?
Making up missed voluntary acts of worship is from Sunnah.
What is the ruling on someone who fasts but does not pray?
A Muslim must be diligent in fulfilling all obligations, and after the Shahadah, prayer is the most important duty.
● If someone abandons prayer out of disregard, they are considered a disbeliever, and their fasting is not accepted.
● If they abandon prayer out of laziness, they are still a Muslim, and their fasting remains valid, but they have committed a grave sin by neglecting prayer.
Is the father a Mahram (Non-marriageable) to his son`s mother-in-law?
The father is a non-Mahram (Marriageable) to his son`s mother-in-law, so it is impermissible for them to look at each other, or to have a seclusion (Khalwah).