A week earlier, 2-year-old twins llannah and Alliya Larry were found dead in their grandmother's car on June 16.
In both cases outside temperatures were in 90s.
Experts said hot car deaths were preventable with simple precautionary steps.
To prevent children from dying while playing in a car, parents should "absolutely keep their cars locked even if in the garage or driveway. That's where these accidents take place," said Janette Fennell, founder and president of KidsandCars.org, an advocacy group.
"Children should not have access to keys and key fobs. They love pushing that button and hearing the car beep," she said.
Parents should create routines that remind them their child is still in the car, she said.
Keep a stuffed animal in the car seat, Fennell suggested. When you place the baby in the seat, move the doll to the front passenger seat, to remind you the child is in the back, she said.
Parents should also leave their cell phone, employee ID, handbag, or another item they will need, on the floor in front of the baby's car seat. "It's important parents always get in the habit of opening the back door and checking they have the baby," Fennell said.