Since you are over 21 and a USC, you are able to sponsor your father for a green card. Your ability to immediately sponsor his wife depend upon when they were married. If before your 18th birthday, then she is considered your step mother and you can separately sponsor her. Otherwise she will need her husband to apply for her once he is a green card holder. It will take several years for her to apply based on that category so she would need to find a different way to reside in the US. until that time- student, work, etc.
Answered on Jan 28th, 2011 at 11:58 AM