I want to marry my girlfriend so she can finally become a legal resident of the U.S. I am a U.S. citizen and she has been living in the States with "no status". We are both college students and we are both dependent on our parents until we graduate in May 2010. We were told we need a co-sponsor in order to be able to fix her situation. What are the requirements of that co-sponsor? I understand he/she has to make over $18,000, but does the co-sponsor have to be related to me? Is the co-sponsor required to do anything other than provide his signature, taxes and etc.?