MISSION, TX – JULY 24: A mother and child, 3, from El Salvador await transport to a processing center for undocumented immigrants after they crossed the Rio Grande into the United States on July 24, 2014 in Mission, Texas. Tens of thousands of immigrant families and unaccompanied minors have crossed illegally into the United States this year and presented themselves to federal agents, causing a humanitarian crisis on the U.S.-Mexico border. (Photo by John Moore/Getty Images)