It depends how the property was titled and it depends on the language of the wills.
If the property was titled between your father and your mother as "in the entireties" (as is usually the case between husband and wife), that would mean that upon your mother's death, the property became your father's fully, and then his will would rule. If it was titled as "tenants in common" or not specified (unlikely, but possible), then your mother's will would dictate her share of the house and your father's will would dictate his share. More than likely, your father's will will control, but it wouldn't hurt to consult with an attorney to be certain.
Answered on Feb 25th, 2013 at 5:19 PM