Each immigrant has his or her own reasons for seeking to move to the United States. Regardless of the reason there are multiple ways in which the goal may be accomplished. For those with family members already residing in the U.S., that may serve a big catalyst. If those individuals have relatives who are citizens of the U.S., they could play an integral role in the immigration process.
People who are citizens of the U.S. may sponsor a relative from another country so that they may obtain a green card and become a lawful permanent resident. Not all relatives are eligible for this process. Specifically those who are eligible to come to the U.S. via this process must be a spouse, a child, a parent or a sibling. Separate petitions must be filed for each relative and evidence of the relationship must accompany the application.
There is of course more to this process. For example a citizen must sign an Affidavit of Support that indicates that the citizen will also be a financial sponsor.
The process is not always as straightforward as it may seem. In many cases immigration matters are extremely complex. Accordingly, whatever the route of immigration you are pursuing, an immigration lawyer is often of assistance. He or she may be aware of programs or laws that could be advantageous to your situation. In the alternative, an immigration attorney might identify potential issues with a petition so that they can be resolved before they become a problem.
Source: U.S. Citizenship and Immigration Services, “I am a U.S. citizen How do I help my relative become a U.S. permanent resident?” Accessed Sept. 19, 2014