At a glance Mississippi averages one death a year from children being left in overheated cars. The national average is 30 deaths a year. Source: University of Mississippi Medical Center

Tyler was outside with a 7-year-old brother who apparently opened the door to the car, Byrd said. The door was shut after Tyler climbed in, Byrd said.

Tyler's parents were inside at the time and each thought the other was watching the child, Byrd said.

"At this time it seems to be a terrible accident," Broadus said.

Tyler was found by a grandmother who lived nearby, Byrd said.

Broadus said the victim apparently was in the car for "a prolonged time."

"It was very, very hot," Broadus said. "We need to caution parents how important it is to watch their children."

The recorded high Sunday was 86 degrees.

In June, a Natchez man was charged in the death of his grandson who was found dead inside a car in Ridgeland. Authorities said Robert Dossett, 61, forgot to drop the child off at day care on his way to work.

But Madison/Rankin District Attorney David Clark said Dossett should not be prosecuted on manslaughter and culpable negligence charges. He said Monday the case won't be presented to a grand jury.

"I completely dismissed the case the day he got out of jail, with the consent of the Ridgeland police chief," Clark said. "I said all charges are dismissed, forever. He didn't commit a crime, and it was an accident. The man was suffering horribly. There was no reason to keep him in jail."

The state averages one death a year from children being left in overheated cars, according to numbers provided by the University of Mississippi Medical Center. The average is 30 nationwide.