The death was not previously revealed by the federal government, only coming to light Wednesday after a CBS News report.
Citing a government spokesman, CBS reported that the girl had history of congenital heart defects and entered an Office of Refugee Resettlement facility in San Antonio last spring while in a "medically fragile" state. She went into a coma following a surgical procedure and died months later in a Nebraska hospital.
"It is unacceptable that the nation is hearing about this tragedy for the first time eight months after her death," said Jess Morales Rocketto, who chairs immigrant-rights group Families Belong Together, "and it raises serious questions about how many other migrant children’s deaths the Trump administration either doesn't know about, doesn't care about or is sweeping under the rug."
U.S. Rep. Joaquin Castro, D-San Antonio, the chair of the Congressional Hispanic Caucus, told CBS the administration appears to have "covered up her death." He said he's demanding more information about the case.
The revelation follows the announcement earlier this week that 16-year-old Carlos Hernández Vásquez of Guatemala died in immigration custody in South Texas after telling officials he felt ill.
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