U.S. Citizenship

Under United States law, U.S. citizenship is automatically granted to any person born within and subject to the jurisdiction of the United States. This includes the territories of Puerto Rico, the Marianas (Guam and the Northern Mariana Islands), and the U.S. Virgin Islands, and also applies to children born elsewhere in the world to U.S. citizens (with certain exceptions). Citizenship Clause of the Fourteenth Amendment to the United States Constitution. The 1868 text states, "All persons born or naturalized in the United States, and subject to the jurisdiction thereof, are citizens of the United States and of the State wherein they reside." This DOES include children born to illegal aliens.
The Pew Hispanic Center estimates that approximately 7.5% of all births in the U.S. (about 300,000 births per year) are to illegal immigrants.[5] The Pew Hispanic Center also estimates that there are 4.5 million children who were born to illegal immigrants that received citizenship via birth in the United States; while the Migration Policy Institute estimates that there are 4.1 million children. Both estimates exclude anyone eighteen and older who might have benefited.

In order to register their children as Mexican nationals, parents must present several documents at the consulate, including the child’s birth certificate, a marriage certificate and other identification for each party involved. The consulate also requires documentation from two witnesses. The process takes about half an hour if all the paperwork is in order, though many families end up having to visit the consulate more than once to file the appropriate documents. Only one parent needs to be a Mexican citizen in order to register their child for dual citizenship.