text: as a us citizen, can i bring my uncles, aunts, cousins, nephews and nieces from mexico?   if you are a us citizen you may petition for the following foreign national relatives to immigrate to the united states; however you must be able to provide proof of the relationships:  * husband or wife; * unmarried child under 21 years old; * unmarried son or daughter over 21; * married son or daughter of any age; * brother or sister, if you are at least 21 years old; or * parent, if you are at least 21 years old.