BRYAN, Tex. — José was 7 years old when they put him on the raft.

The smugglers were sending him across the Rio Grande to reunite with his mother, who had left him back in Honduras two years earlier and moved to Texas. He boarded the raft with his sole possession: a piece of laminated paper bearing her phone number and address.

His mother had borrowed $3,500 from a cousin and a friend to pay the coyotes. Her brother handed José over to the men, who tried to scare the boy into staying quiet as the raft pushed off from the Mexican shore. “They were telling me that they were going to report me to my country,” José said. “But I didn’t believe him.”

What the boy didn’t know was that reaching his mother would be much harder than finding a Border Patrol agent, spending a few days in custody and then looking for his mother’s house, as he had been told to do. He found the Border Patrol, all right, but instead of being handed over to his mother, José was sent to a foster care facility in New York, where he was held for nearly eight months as his mother tried to win permission for his release. She didn’t succeed until last month.

[Crossing the Border newsletter: Waiting at the Whataburger]

José was what the federal government calls an “unaccompanied minor” — an abstract clinical description for a dangerously specific human drama that has been playing out in ever-larger numbers along the southwest border.