When he landed in Michigan in late May, all the weary little boy carried was a trash bag stuffed with dirty clothes from his dayslong trek across Mexico and two small pieces of paper — one a stick-figure drawing of his family from Honduras, the other a sketch of his father, who had been arrested and led away after they arrived at the U.S. border in El Paso.

A U.S. government escort handed over the 5-year-old child, identified on his travel documents as José, to the woman whose family was entrusted with caring for him. He refused to take her hand. He did not cry. He was silent on the ride “home.”

The first few nights, he cried himself to sleep. Then it turned into “just moaning and moaning,” said Janice, his foster mother. He recently slept through the night for the first time, though he still insists on tucking the family pictures under his pillow.

José’s separation from his father is part of the Trump administration’s latest and most widely debated border enforcement policy. Last month, Attorney General Jeff Sessions announced that the government would criminally prosecute everyone who crosses the border illegally, a directive that is already leading to the breakup of hundreds of migrant families and channeling children into shelters and foster homes across the country.

The goal, according to administration officials, is to discourage Central American families from making the perilous journey to the United States’ southwestern border, where they have been arriving in swelling numbers this year to claim asylum.

In just the first two weeks under President Donald Trump’s new policy, 638 parents who arrived with 658 children had been prosecuted, administration officials told Congress.

Kirstjen Nielsen, the homeland security secretary, emphasized that separating families was not the aim but merely the effect of a decision to step up prosecutions of those who cross the border illegally. “We do not have a policy to separate children from their parents. Our policy is, if you break the law we will prosecute you,” she told the Senate Homeland Security and Governmental Affairs Committee on May 15.

She said the Trump administration is doing a better job than its predecessors in ensuring that migrant children are placed with sponsors who are carefully screened. “We can make sure that the children go to people who are actually family members and who are not traffickers and who won’t abuse them,” she said.

Whether the policy will succeed as a deterrent remains an open question. What is clear is that it is creating heartbreak and trauma for those subjected to it, with parents and children often unaware of one another’s whereabouts.

Since José’s arrival in Michigan, family members said, a day has not gone by when the boy has failed to ask in Spanish, “When will I see my papa?”

They tell him the truth. They do not know. No one knows.

José’s father is in detention, and parent and child until this week had not spoken since they were taken into the custody of U.S. authorities.

“I am watching history happen before my eyes. It’s horrendous,” said foster mom Janice, 53.

Janice, her husband, Chris, and their two teenage daughters are among a number of families who have in recent years provided a temporary home, called transitional foster care, to minors seeking refuge in the United States, usually after fleeing violence and economic uncertainty in Honduras, El Salvador or Guatemala.

In the past two years, 12 children have occupied the room upstairs with its soothing white and light-blue walls and twin beds with colorful bedding. All had arrived in the United States alone and remained in the family’s care for a few weeks or months until a long-term sponsor already in the country, often a relative, was identified and cleared by the authorities to receive them.

“They had access to their parents on a daily basis,” Janice said. “They talked to them on the phone. We have done video chats with Mom and Dad and siblings with every placement — except now.”

José is the first child they have hosted who crossed the border with a parent, rather than alone, then was forcibly separated and left with no ability to contact them. On his flight to Michigan were two other Central American boys in similar circumstances who were placed with families in the area.

The majority of youths apprehended at the border over the past several years have been housed in government shelters, and most of them are teenagers who came alone, often expecting to join family members already in the United States.

About 11,000 children are in these facilities, which are at 95 percent capacity, according to Kenneth Wolfe, a spokesman for the Department of Health and Human Services. The department has reserved an additional 1,218 beds in various places for migrant children, including some at military bases, he said.

On May 10, three days after Sessions announced the zero-tolerance policy, the government issued a call for proposals from “shelter care providers, including group homes and transitional foster care” in anticipation of a surge in children separated from their parents who would require housing.

In response, Bethany Christian Services, which is coordinating foster placements for about 100 migrant children in Michigan and Maryland, including José’s, is planning to expand to several other states. Families receive a stipend of about $400 a month to defray the costs of taking care of a child.

“We don’t want to have to ramp up,” said Chris Palusky, president of Bethany. “We would prefer these kids stay with their families; they should not be separated. But being in a loving foster home is better than being on a military base.”

Earlier this week, José spoke with his parents for the first time since their lives had diverged. The phone calls were separate: His father remains in detention, and his mother is in Honduras.

The calls went smoothly, according to his case manager.

But they changed everything. Somehow, it had sunk in that there was no way of knowing when he would see his family. “It triggered all the separation trauma again,” said Janice.

She tried to offer him his toys, but he erupted in anger, screaming and crying at the kitchen table for almost an hour.

“It was really hard to watch. The look on his face was anguish,” said Janice, her voice breaking.

When his fury subsided, the boy collapsed on the kitchen floor, still sobbing. “Mama, Papa,” he said, over and over.

Nearby lay the drawings of his family, which he had flung on the floor.