Earlier this week, news broke that some of the nearly three thousand immigrant children who have been taken from their parents at the border are being transferred to “tender-age” shelters run by the Office of Refugee Resettlement (O.R.R.), an office within the Department of Health and Human Services (H.H.S.). The A.P. reported that children—many of them age five or younger, some of them babies and toddlers—have been sent to three facilities in southern Texas; a fourth is apparently under construction in Houston. Pamela Florian, a lawyer who works with young children in O.R.R. custody in Arizona, told me that she and her colleagues at the Florence Immigrant and Refugee Rights Project have seen a dramatic spike in the population of young children at the shelters that they visit. “Every single shelter has tender-age kids now,” she said. On Wednesday, Trump signed an executive order to end the policy of separating parents and children, and called instead for the detention of complete families at the border—a practice that would violate existing law. (On Thursday, the Washington Post reported that Customs and Border Protection would temporarily halt referrals for the criminal prosecution of parents who cross the border with children.) But the end of the family-separation policy does nothing to address or resolve the situation of the thousands of children who have already entered government custody.

In the past, “there have been really small numbers of tender-age children that came into O.R.R. care—minuscule,” Bob Carey, who served as a director of the O.R.R. under President Obama, told me. “Usually, if they came in, they were in the company of an older sibling, or a pregnant teen in O.R.R. care gave birth, and then the child was with his or her mother, not unaccompanied.” Carey and other former officials I have spoken with over the past few days warned that the separation policy is putting unprecedented strain on a system that is not equipped to handle the volume and needs of the young children who have now been placed in its care.

It’s worth clarifying that O.R.R. shelters are a far cry from the cage-filled, blindingly lit warehouses, with their thin rubber mats and Mylar blankets, that have recently been the subject of much public outrage. Those facilities are run by Customs and Border Protection (C.B.P.), and children are supposed to spend no more than three days in one before being moved into O.R.R. care. O.R.R. shelters are generally equipped with dormitories, cafeterias, communal spaces, play areas, classrooms, and also counselling services. There are mandated child-to-staff ratios. Some shelters have explicit provisions to care for young children. “There are certainly shelters that have been designed with nurseries and cribs, and have extra staff members who meet special licensing requirements,” a former H.H.S official told me. “But that’s not the majority of the system. Most shelters are designed for teen-agers, boys in particular.”

Converting a facility meant to house teen-agers into one meant for toddlers is not a straightforward task. “Staffing up to care for toddlers and preverbal kids is a time-consuming process, because of licensing requirements, and because of the extra training that staff need,” the former official said. “It’s not just taking folks who have been dealing with sixteen- and seventeen-year-old boys and saying, ‘It’s your job to change a diaper and try to comfort a kid ripped from his or her mom.’ ” Carey told me, “When you’re talking about children who have been forcibly removed from a parent, the trauma is going to be greater, and so are the challenges of caring for those children.”

Cost is another major problem. “It takes time to develop capacity, and it takes a lot of money as well. And, when you’re developing care capacity on an emergency basis, it’s very, very expensive to do,” Carey said. “They need bilingual workers. Some kids speak indigenous languages, so that’s an issue as well. Then there are children who may not yet be verbal, and who aren’t able to articulate their needs, and that will have to be addressed.”

By definition, O.R.R. shelters are not designed for long-term residency. According to Flores v. Reno, a legal settlement in 1997 that established baseline conditions for the treatment of minors in government custody, the government is obligated to hold minors in “the least restrictive setting” according to their needs, and to release them into the custody of a parent or other family member “without unnecessary delay.” One terrible irony of the current crisis is that a government office whose explicit goal is to reunify children with their families is now being used to hold children who have entered its jurisdiction because the government has forcibly removed them from their parents’ care.

Already, the O.R.R. is housing children for much longer stays than it is accustomed to doing. “In the Obama Administration, time in O.R.R. care was approximately a month, on average. We worried a lot about variations of a few days. There have been reports that stays are closer to two months now,” Maria Cancian, who between 2015 and 2016 served as H.H.S.’s Deputy Assistant Secretary for Policy in the Administration for Children and Families, told me. Such delays inevitably lead to overcrowding and a lack of space. Often, the O.R.R. prefers to send children, particularly young ones, into foster care, so that the child can benefit from a stable family setting while waiting for placement with a more permanent guardian. But many such programs are currently overextended.

Even if a child has another relative who might be able to take custody, the current fearful, prosecutorial climate poses an additional challenge. “In the prior Administration, we would sometimes know about the immigration status of sponsors, and that was a concern to the extent that the sponsor could be deported,” Cancian said. “We wanted to make sure that there was a safety plan, an alternate placement available to the child should the sponsor be deported. But our mandate was to act in the best interest of the child. We are not an immigration-enforcement agency.” Now, amid reports that H.H.S. has agreed to share sponsors’ information with ICE, undocumented adults have reason to fear stepping forward. “If we’re saying to people, ‘Come pick up your children, and, by the way, we need to know how to reach you, and we’re going to use that information to deport you,’ not very many people are going to come forward to pick up their kids,” Cancian said.

It has become clear that the Trump Administration has put no protocols in place for keeping track of children and their parents as they move through separate systems, or for facilitating their eventual reunification. Perversely, reunification may prove to be more difficult for the children separated from their families inside of the U.S. than for the children who have braved the dangerous journey to the United States alone. In the past, the former H.H.S. official told me, small children who arrived unaccompanied in the United States generally carried identification, “or had it literally attached to them. Maybe a piece of paper was taped to them, identifying who they are, and who they want to be reunited with in the United States.” In March, 2017, for instance, Border Patrol agents found a four-year-old Guatemalan girl who had been abandoned by smugglers in the California desert. She was carrying a birth certificate and information about the location of her parents. Parents who arrived at the border with their children over the past few months may not have anticipated taking such precautions.