Of the 14,300 migrant children in U.S. custody, some 5,400 are detained in shelters holding more than 1,000 children, according to an Associated Press report.
The head of Harvard University's Center on the Developing Child called the situation "a moral disaster."
The wait for migrant children to be placed with parents or relatives has doubled because the Trump administration required prospective sponsors to undergo fingerprinting and "extreme vetting."
On Wednesday, the Office of Refugee Resettlement announced a change in policy that would now require only parents be fingerprinted rather than everyone in a household.