Units with the Harris County Sheriff’s Office responded to the 13700 block of Blair Hill Lane and found the boy unresponsive, Fox Houston reported.
He was pronounced dead at the scene.
Sheriff Ed Gonzalez said the mother and her 8-year-old daughter went inside a home when the mother noticed the child wasn’t inside hours later.
“Shed frantically ran outside and discovered the 5-year-old still buckled in his car seat,” he told reporters. The death happened as the family was preparing to celebrate the girl’s birthday.
The mother told investigators the child knows how to unbuckle himself and get out of the car. The vehicle was described as a “loaner car,” the news outlet said.
Authorities did not say if the mother will face charges. In 2021, 23 children died from hot car deaths, according to the National Safety Council. In 2018 and 2019, a record 53 children died after being left in a hot vehicle, the group said.