Protests have been held at the US-Mexico border after a seven-year-old girl who travelled north from Guatemala died in custody.
Jakelin Caal Maquin was among a group of 163 people who handed themselves over to patrol agents on 6 December, and she later died of dehydration and shock.
Customs and Border Protection (CBP) told The Washington Post that the girl had not had anything to eat or drink in several days and was flown to El Paso hospital in west Texas after she began to have seizures.
That version of events is disputed by her father, Nery Caal, whose lawyer has insisted that he ensured Jakelin was well fed and watered throughout their 2,000 mile journey from their home.
In a statement read out by Ruben Garcia, the director of Texas migrant shelter Annunciation House, the attorney said the family was seeking "an objective and thorough investigation" into why Jakelin died.
"Jakelin and her father came to the US seeking something that thousands have been seeking for years – an escape from the dangerous situation in their home country," the statement said.
"This was their right under US and international law. But it is a journey that had resulted in tragedy.
"The family is seeking an objective and thorough investigation and are asking that investigators will assess this incident within nationally recognised standards for the arrest and custody of children.
"The family intends to assist in such an investigation into the cause and circumstances of Jakelin's death."
As well as the dispute over whether Jakelin had been fed, other points of contention include the fact that Mr Caal was allegedly asked to sign vital forms in English – a language he does not speak or understand.
There has also been no statement from the medical examiner who conducted a post-mortem on Jakelin.
Her death has raised further questions about the treatment of those detained at the border, with Democrat politicians and activists having raised concerns regarding the condition of the holding cells.
Record numbers of parents travelling with children are being apprehended trying to cross the border with Mexico, which has been a key part of the hard-line immigration policies employed by US President Donald Trump.
In November, border officers detained 25,172 members of "family units" – the highest monthly number ever recorded.
In a statement responding to the death of Jakelin, the US Department of Homeland Security said: "As we have always said, travelling north illegally is extremely dangerous.
"Drug cartels, human smugglers and the elements pose deadly risks to anyone who comes across the border illegally.
"Once again, we are begging parents not to put themselves or their children at risk attempting to enter illegally."
Mr Caal is reported to still be keen to stay in the US and find work.
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Jakelin's mother, Claudia Maquin, said her daughter had dreamed of starting a new life with him and being able send money back to their impoverished family back home.
Mr Caal remains in El Paso, having left his home in the poverty-ridden Raxruha area of Guatemala on 1 December.