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This might help you. I copied some information from www.uscis.gov. If still unclear please visit this website for more infortmation.
U.S. citizens who want their relatives to immigrate to the United States can file a Form I-130, Petition for Alien Relative, for their spouse, children and if the U.S. citizen is at least 21 years old, their parents and brothers or sisters.
“Immediate relatives” of a U.S. citizen, defined as one’s spouse, unmarried children under the age of 21, and parents, always have a visa number immediately available and are discussed in the “Green Card for an Immediate Relative of a U.S. Citizen” link to the left.
If your relationship does not qualify you as an immediate relative of a U.S. citizen, then you may be in what is called a “family preference category.” Eligible relatives include:
- Unmarried sons or daughters over the age of 21
- Married child(ren) of any age
- Brothers and sisters (if the U.S. citizen petitioner is over the age of 21)
Congress has limited the number of relatives who may immigrate under these categories each year so there is usually a waiting period before an immigrant visa number becomes available.
This page discusses the steps required to get a green card (permanent residence) for relatives of a U.S. citizen in a preference category.
Get a Green Card While Inside the United States
If you are currently in the United States and are one of the specified categories of relatives of a U.S. citizen in a preference category, you may be able to become a permanent resident in two steps.
- Step One – Your U.S. citizen family member (sponsor) must file the Form I-130, Petition for Alien Relative, for you and it must be approved. You must wait for your priority date in your immigrant visa category to become current. Your priority date is the date when the Form I-130 is properly filed (with correct fee and signature) on your behalf by your U.S. citizen relative. For more information on priority dates, see the “Visa Availability & Priority Dates” link to the left under “Green Card Processes & Procedures.”
- Step Two – Once the priority date in your visa category is current, you may file for Adjustment of Status with Form I-485, Application to Register Permanent Residence or Adjust Status. Adjustment of Status is the process you go through to become a Permanent Resident. For more information, see the “Adjustment of Status” link to the left under “Green Card Processes & Procedures.”
Get a Green Card While Outside the United States
If you are currently outside the United States and are one of the specified categories of relatives of a U.S. citizen in a preference category, you can become a permanent resident through consular processing. Consular processing is when we work with the U.S. Department of State to issue a visa on an approved Form I-130 petition when a visa is available. In this process the Department of State will issue you a visa. If approved, you may then travel on the visa and will officially become a permanent resident when admitted at a U.S. port of entry. For information on consular processing see the link to the left under “Green Card Processes & Procedures.”