Hours after President Trump declared in the White House Rose Garden that he doesn’t “do coverups,” his administration revealed that it had been hiding the death of a migrant girl at the border for the past eight months. On Thursday evening, CBS News reported that a 10-year-old girl from El Salvador died last September while under the care of the government. The Department of Health and Human Services confirmed the death, which had not been previously disclosed.

HHS spokesman Mark Weber explained that the girl had a history of heart problems and was in a “medically fragile” state when she arrived at an Office of Refugee Resettlement facility last March. The girl’s name was not released, and it’s unclear why the death was not previously reported. “I have not seen any indication that the Trump administration disclosed the death of this young girl to the public or even to Congress,” Rep. Joaquín Castro (D-TX) told CBS. “And if that’s the case, they covered up her death for eight months, even though we were actively asking the question about whether any child had died or been seriously injured. We began asking that question last fall.”

At least seven children are known to have died in immigration custody since last year, after almost a decade in which no child reportedly died while in the custody of U.S. Customs and Border Protection.

The string of cases continue to raise questions around the conditions in which migrant children are being kept at a time when a growing number of migrants, many of them Central American parents with children, are presenting themselves at the border to seek asylum.

Aside from the fact that children may have underlying health conditions, most are reaching the United States after arduous journeys during which they have had little access to clean shelter and proper provisions. Many are leaving impoverished and drought-stricken regions.

For the past year and a half, Dr. Eric Russell has been traveling from Houston to McAllen, Texas, every three months or so to volunteer at the Catholic Charities Humanitarian Respite Center, a first stop for many asylum-seeking migrants who’ve been released by U.S. Customs and Border Protection in the Rio Grande Valley.

During his most recent visit to the clinic in April, when he saw more than 150 migrants, he noted a troubling new trend: a number of people reported that their medication had been taken from them by U.S. border officials.

“I had a few adults that came who had high blood pressure, who had their blood pressure medications taken from them and, not surprisingly, their blood pressure was elevated,” Russell told Yahoo News. “There was a couple of adults that had diabetes that had their diabetes medicines taken from them, and wanted to come in because they were worried about their blood sugar. And, not surprisingly, their blood sugar was elevated.”

For Russell, a pediatric emergency medicine physician, the patient who stood out the most during that visit was a boy of 8 or 9 with a history of seizures. According to his mother, the child had been on a long-term seizure medicine in their home country, but the medication had been taken from him upon entering the Border Patrol custody in McAllen and never returned.

“The mom came to the clinic because she was concerned that he was going to have a seizure,” said Russell. He wasn’t sure exactly how long they’d been in custody — “usually it's a matter of days,” he said, “but with seizure medicines, that’s enough.”