If you are either a US citizen or a lawful permanent resident and have relatives who are willing to permanently move to the United States, you can benefit from the family based immigration.
If you are a U.S. citizen, the following relatives are eligible under family based category:
• Your spouse
• Your unmarried children under 21 years of age
• Your unmarried sons or daughters 21 years of age or older
• Your married sons or daughters of any age
• Your brothers or sisters (you must be 21 years of age or older); and
• Your mother or father (you must be 21 years of age or older)
If you are a lawful permanent resident of the United States, you can petition for:
• Your spouse
• Your unmarried child under 21 years of age
• Your unmarried son or daughter 21 years of age or older.