LAKELAND, Fla. — A Florida couple whose 18-month-old girl died unattended in a car left in sizzling heat after they returned from a July 4th party have been charged in connection with the child’s death, officials said.

Joel and Jazmine Rondon, both 33, face one felony count of aggravated manslaughter of a child. Polk County Sheriff Grady Judd said Thursday afternoon that he thinks the “horrible, tragic death” of the toddler was not an accident, but negligence caused by the couple’s use of illegal drugs and alcohol.

“That’s a disaster waiting to happen,” he said. “Here’s one more person who is dead — a baby who can’t help itself — because of the abuse of drugs.”

The toddler was at least the 10th child to die after being left a hot car this year, according to advocacy group Kids and Car Safety, including five children who died in Florida.

What happened to the toddler?

Judd said deputies discovered the Rondons took three children — ages 8, 6, and 18 months — out to a Fourth of July celebration in downtown Lakeland, about 60 miles southwest of Orlando. They returned to their home at about 3 a.m. the next morning. The couple began unloading food and other items from their Hyundai Elantra.

Jazmine Rondon asked her husband to bring the toddler inside while she helped the older two children, Judd said. The right rear passenger door of the car was open at the time.

Joel Rondon told deputies he brought items inside the house and when he went back outside, he saw all the vehicle’s doors were closed. He assumed that his wife had gotten the toddler out and went to lie down, according to the sheriff.