If you are an immediate relative of a US citizen, you can become a lawful permanent resident (get a Green Card) based on your family relationship. You must be legally married to your spouse; Your spouse must be willing to sponsor your green card application; You must be at least 18 years old.If you are a U.S. citizen, you have the opportunity to sponsor your immediate relatives for a green card through the Form I130 petition. The foreign spouse will need to complete a medical exam, consular interview, and receive criminal record clearance prior to a marriage visa being issued. U.S. citizens may petition a spouse, child, parent, or sibling. Permanent residents and U.S. nationals may only petition a spouse or unmarried child (any age). Petitioner: This is the individual who fills out the form to get the green card process started for a family member abroad. Two petitions are required: Petition for Alien Relative, Form I-130, and Petition for Alien Fiancé(e), Form I-129F. Learn more. Fiancé(e). If your spouse is a U.S. citizen, you, too, may be eligible for U.S. citizenship after receiving your own green card (residency) through marriage.