Memphis, Tennessee – Six‑year‑old Winter Jones was supposed to be taken to elementary school by the school bus last Thursday. Her parents never imagined that they would see their daughter for the last time that morning due to a tragic accident.

On Thursday morning, her father, Bryan Jones, dropped off little Winter at a daycare in a Memphis suburb. From there, she took the school bus as usual to Macon Hall Elementary, as Fox 8 reports.

But when she arrived, the girl, who has been diagnosed with autism, didn't get off the bus. No one noticed that Winter had been sitting in the vehicle for several hours in the sweltering summer heat.

"No one knew that she was still on the bus until they got back on the bus and got ready to go and pick up the students from school," Christopher Jones, Winter's uncle, said.

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Memphis police confirmed that around 3:30 PM local time, a minor was found who needed medical attention. She was taken to the hospital in critical condition.

There, Winter died, according to her father, with a body temperature of 109 degrees.

Because of her neurological disorder, the girl doesn't speak, so she couldn't draw attention to herself.

"She couldn't advocate for herself. She couldn't open her mouth and say, 'Hey, I'm still on the bus,' or anything like that," her uncle emphasized.

Christopher Jones can't understand why the school facilities don't take precautions to prevent something like this. The Memphis Shelby County school board wants to investigate the case.