Transcript for Family disputing how 7-year-old migrant girl died in US custody

helps poliind berret Tom? Mar, thank Yo Next, now developments after the 7-year died in U. Custod her family callingor an inig even H the thank oicials for trying to save her life. The girl, one ofdr every yeartross the border. Here's lk. Reporter: Tonight, the family of 7-yeaold jakelin Caal maquin, calling for a fair investign 7-year-old's tragic death while in border patrol custody. Thchild is T most painful experience that a jakelin's famiow for days, saying she appeared when she crossnto the U.S. Witr father. , Still in Guatemala, says jakelin and her father were asylum in the U.S. But T hours afr arriving at border control, the little girl began to vomit. It would be 90utes before sht sistance. Time, she sn't breathing.temperature, 105.9 des.shthhospital. Accoinovernment report obtained by ABC news, nearly 300 people he Ed trying to cross the u.s./mexico border T year the commisers border protection says they are understaffed. Our border patrolti and ports of entry were built to hand mostly ma single ADTs custody, T families children. Reporter: Democrats are calling for reform, while erru nistration say her death should a warning to other migrant parents. I cannot stress how dangerous this journey is when migrants chase to come here illegally. Reporter: Several senators say they want to know why like this one have inffical staffs. And Yoo so long for her to receive aid. But the father says heves offis did all they could, and expresseeciation F

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