The girls, ages 1 and 2, were gravely ill when they arrived at the hospital. According to investigators, their mother made it sound like they’d collapsed mysteriously on an otherwise idyllic day.

“There’s a lake close to where they were,” Kerr County Sheriff Rusty Hierholzer told The Washington Post. “She said the little girls were walking around smelling flowers. She didn’t know if maybe they’d ingested or touched a poisonous flower.”

That was a lie, Hierholzer said. The sisters’ final day of consciousness had not been spent among flowers, he said, but rather intentionally trapped inside an SUV that grew hotter by the hour in “the most horrific case of child endangerment that I have seen in the 37 years that I have been in law enforcement.”

It is, sadly, not so rare for children to be left alone in hot cars as the sun bakes them alive. Law enforcement and first responders see multiple cases each year. But “most of them are accidents,” Hierholzer said.

“She knew those kids were back there. She left them in that car,” he said.

Amanda Hawkins, 19, had not taken her daughters to a park as she first claimed, authorities say, but rather to a friend’s house on Tuesday night, where she got out of the vehicle and left her children alone until noon the next day.

“About 15 to 18 hours,” Hierholzer said. “Windows rolled up. Ninety degree weather.”

The sheriff didn’t say exactly what Hawkins and her friends were doing in the house. But some time Tuesday evening, he said, someone heard the girls crying outside and asked Hawkins to bring them in.

“She said: ‘No, it’s fine. They’ll cry themselves to sleep,'” Hierholzer said.

The mother had arrived to the house with a teenage friend, who early in the morning went to sleep in the car with the children, according to the sheriff.

But “he went back inside,” the sheriff said. The children remained in the car as the sun rose over the Hill Country county northwest of San Antonio.

Their names were Brynn Hawkins, 1, and Addyson Overgard-Eddy — a 2-year-old who loved to help adults by fetching items for them, a friend of the mother told KSAT.

The mother finally returned to the SUV about noon on Wednesday, Hierholzer said. “Best we can tell, they were probably unresponsive.”

They were alive, still. But instead of seeking help immediately, authorities say, the mother bathed and re-dressed her children — attempting to cover up what happened until their conditions left no option but the hospital and a lie about flowers.

“It unraveled pretty quickly,” the sheriff told Fox 29. He said Hawkins has since confessed. It was unclear if she has an attorney.

Late Thursday afternoon, hospital staff in San Antonio unplugged Brynn and Addyson’s ventilators, having concluded that they were beyond saving.

Hawkins, who could not be reached, was jailed on two counts of abandoning or endangering a child — one for each daughter — and could face more charges after the police find out more about their last hours.

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