CBP typically detains immigrants for no more than a few days when they cross the border before either releasing them or turning them over to U.S. Immigration and Customs Enforcement for longer-term detention.
Staff diagnosed him with a cold but later discovered a fever.
During the evening on December 24, however, officials said the boy experienced nausea and vomiting, and was again transferred to the same hospital, where he died the next day. The Guatemalan government has been notified and is in touch with the father and any family members in Guatemala, CBP said. Jakelin Caal Maquin and her father, Nery Caal, were apprehended by Border Patrol agents in the New Mexico desert on December 6, as part of a larger group of 163 illegal aliens.
Caal's wake was held on Monday, Christmas Eve, in her family's village.
"Many questions remain unanswered, including how many children have died in CBP custody", Castro said.
USA authorities have informed Guatemalan officials of the death.
Jakelin was crossing the US-Mexico border with her father as part of the caravan of Central American migrants.
Marco Ugarte Migrant Child's Death Requires Separate Probe Independent of DHS- US Lawyers
The US government is now shut down due to an impasse between Donald Trump and the Senate over $5 billion (Sh500 billion) of funding the president is demanding to build a border wall between the US and Mexico. He died at the hospital shortly after midnight, CBP said, and the official cause of death is not known.
An investigation into CBP actions will be conducted by the agency's Office of Professional Responsibility, the news release said.
The death of the second child in the agency custody reiterated the criticism of the efforts by President Trump, whose fight for the border wall led to the shutdown of the government thanks to Democrats' opposition, to curb illegal immigration. While in the hospital, the girl was revived after going into cardiac arrest but she died less than 24 hours later.
Guatemala called on United States authorities to conduct a "clear" investigation of the death, adding that "medical reports have been requested.to clarify the cause of death of the child".
Both were taken to a hospital in New Mexico.
Caal's death is being investigated by the Department of Homeland Security's Inspector General, which looks into accusations of misconduct by the agency's employees. The White House did not immediately comment on the boy's death Tuesday.More news: Hector Bellerin: Arsenal defender out for 'some weeks'
More news: Jurgen Klopp responds to Jose Mourinho's trophy jibe
More news: Who is a registered sex offender