Q 4:
Should my wife wear the Hijab (Veil) in the presence of my foster father?
A:
Your foster father is regarded as your father, so your wife does not have to wear the Hijab in his presence acting upon the saying of Allah (Exalted be He):
...the wives of your sons who (spring) from your own loins
This includes the wife of the foster-son according to the saying of the Messenger (peace be upon him):
Foster relations are treated like blood relations (in marital affairs).
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.