If you want to sponsor someone for a family-based green card, you need to provide proof of a U.S. domicile in your Affidavit of Support (Form I-864). If you're planning to petition a family member for a green card, you'll most likely need to prepare Form I864, Affidavit of Support.Typically, in order to claim US domicile, the Affidavit of Support sponsor must be residing in the United States. Certain visas and other immigration documents allow you to establish a domicile in the United States and thus in North Carolina. (3). A valid North Carolina motor vehicle registration in the applicant's name and showing the applicant's current address. (4). How Do I Fill Out an Affidavit of Domicile? ​The N.C. Division of Motor Vehicles recognizes the documents below as proof of North Carolina residency. Download a proof of residency letter template for family members, notarized or non-notarized, tailored for legal use. Learn how to prove your U.S. domicile for a family visa with our stepbystep guide. Essential documents and tips to ensure visa approval.