"An unprecedented number of unaccompanied migrant children are at risk of spending the rest of their childhoods in federal custody," CBS News reported Tuesday evening, citing an interview with the head of the Health and Human Services Department's Office of Refugee Resettlement (ORR) and a tour of an ORR detention center outside Brownsville, Texas. At least one migrant child has been in U.S. custody going on four years, CBS News' Manuel Bojorquez reports.

More than 4,000 of the 10,100 "unaccompanied" children currently in ORR custody have been designated Category 4 cases, meaning they have no identified sponsor to host them in the U.S., ORR director Jonathan Hayes told CBS News in June. If they aren't released to a suitable sponsor by their 18th birthday, the migrant children are handed over to Immigration and Customs Enforcement custody, usually a precursor to deportation.

The number of Category 4 child migrants has risen sharply under President Trump, and the percentage of children released from ORR custody dropped dramatically in fiscal 2018, agency records show. Former ORR officials said Trump's hardline immigration policies and onerous sponsorship requirements have prevented relatives from stepping up to request custody of the detained children. Ricardo de Anda, a Texas lawyer who successfully sued ORR to allow a Category 4 migrant to go live with a sponsor family, said "the reason children are stacking up in these detention camps is because ORR does not allow qualified American families to take these children in."

Life for children housed at the 168 ORR facilities in 23 states is unstable and sometimes dehumanizing, lawyers and former ORR officials tell CBS News. Under the Flores Agreement, migrant children must be released to suitable sponsors as soon as possible, but due to the uptick in Category 4 designations, "they could be indefinitely in our custody, which is not a healthy situation for children," former ORR Director Bob Carey tells CBS News. "And these children are for the most part already traumatized." Peter Weber