One of the primary goals of the U.S. immigration laws is to reunite families. That’s why both U.S. citizens and U.S. lawful permanent residents have the option of petitioning for (often called sponsoring) close members of their family, such as spouses, children, and (for U.S. citizens only) parents and siblings.
However, whom they may petition for, and how soon the intending immigrant (the “beneficiary”) will actually receive an immigrant visa or U.S. green card, varies depending on the status of the petitioner, the family relationship, and the immigrant’s country of origin.
Also, the law sets limits on who can be petitioned for. In no instance, for example, can a U.S. citizen or green card holder petition directly for an aunt, uncle, grandparent, grandchild, niece or nephew, or more extended family member.