The great dream of petition to our closest relatives, according to current immigration law, u.s. citizens and legal permanent residents can sponsor certain family members to obtain legal permanent residence.

The family family relationship immediately with a citizen of the united States are:

• Spouses of u.s. citizens.
• Unmarried children under 21 of u.s. citizens.
• Orphans adopted abroad.
• Orphans to be adopted in the U.S. by u.s. citizens.
• Parents of u.s. citizens who are at least 21 years of age.

Now, there are other categories of relatives, specific, more distant, a us citizen and some specific relationships with a lawful permanent resident (LPR), which have limitations of available visas. 

• Family first preference F1: Unmarried sons and daughters of u.s. citizens, their spouses and their children. (About 9 years of waiting for a visa to become available).
• Family second preference F2:
        F2A: Spouses, minor children (under age 21 years old or of legal residents. (Approximately 6 years of waiting for a visa to become available).
        F2B: unmarried sons and daughters over 21 years of legal residents. (About 9 years of waiting for a visa to become available).
• Tercera preferencia familiar F3: Hijos e hijas casados de ciudadanos estadounidenses y sus cónyuges e hijos menores de edad. (Aproximadamente 15 años de espera para una visa disponible).
• Cuarta Preferencia Familiar F4: Hermanos y hermanas de ciudadanos estadounidenses y sus cónyuges e hijos menores, siempre que los ciudadanos estadounidenses tengan al menos 21 años. (Aproximadamente 17 años de espera para una visa disponible).

  The availability can be checked in the monthly visa bulletin