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In May, the Trump administration rolled out a program it had been testing since last summer to charge everyone crossing the U.S.-Mexico border without proper documents with illegal entry, even asylum-seekers, a policy that "ends up systematically separating families because children can't go with their parents who are being detained by the U.S. Marshals," BuzzFeed News' Adolfo Flores explains. "But people charged with illegal entry go before a judge within days or weeks of their detention and are usually sentenced to time served for the misdemeanor. There appears to be no set procedure for what happens with parent and child after that."

Once the children are separated, they are handed over to the Health and Human Services Department's Office of Refugee Resettlement (ORR) "and treated as though they traveled to the U.S. alone," The New Yorker's Jonathan Blitzer adds. "No protocols have been put in place for keeping track of parents and children concurrently, for keeping parents and children in contact with each other while they are separated, or for eventually reuniting them. Immigration lawyers, public defenders, and advocates along the border have been trying to fill the void."

Immigrations and Customs Enforcement (ICE) spokeswoman Danielle Bennett told BuzzFeed News that "reunification typically does not occur until the removal stage of the process," and "the logistics of the reunification are made on a case-by-case basis." She declined to provide any statistics or give any examples of children successfully reunited with parents, saying, "We don't have any metrics to provide at this point and we wouldn't proactively give examples of this." Homeland Security Secretary Kirstjen Nielsen doesn't seem clear on some details, either.

Immigrant advocates say if there is a policy to track or reunite families, it isn't working on the ground.