BROWNSVILLE, Texas (AP) — Paying a smuggler, Edgar Mejia could afford to take only one child with him to the United States. He chose his 3-year-old "warrior" son, leaving his 7- and 12-year-olds with their mother in Honduras.

"Pitifully, I had use him like a passport to get here," Mejia said last week after picking up milk from volunteers at a Brownsville, Texas, bus station for the last leg of their journey to join relatives in Atlanta. "I am here because of him."

Mejia, 32, and his son, who paid a smuggler $6,000 for a "new dream" that Honduras couldn't provide, are among the Border Patrol's...