Though there is a general process for family-based immigration to the United States, every case is different. Special restrictions apply, for instance, if the foreign relative has a serious contagious disease, has committed certain crimes or is otherwise excludable. There is also an additional step for foreign nationals who marry U.S. citizens or green card holders. The person sponsoring a foreign family member must prove to the INS that he or she is either a green card holder or a U.S. citizen. If a U.S. citizen, include with the I-130 a copy of a birth certificate, a certificate of naturalization or a copy of a valid U.S. passport.
Permanent residents can send a copy of their green card.
The U.S. citizen or green card holder must also prove his or her relationship to the foreign family member. If the U.S. citizen or green card holder is married to a foreign national, he or she should supply a copy of the marriage certificate. To prove that the foreign green card applicant is eligible to immigrate to the United States, he or she must fill out form OF-230, Application for Immigrant Visa and Alien Registration. The form is used to collect your biographical data and to help determine whether you're eligible for a green card. Once the INS receives the I-130 visa petition, it will be approved or denied.