What Documents Do You Need to Prove Family Relationship?
You have to prove that there is a family relationship between you and your relative. If you are filing for:
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7. A father: Submit a copy of your birth certificate showing the names of both parents. Also give a copy of your parents' marriage certificate establishing that your father was married to your mother before you were born, and copies of documents showing that any prior marriages of either your father or mother were legally terminated.