About 20 children in the U.S. have died this year alone from being left in hot cars.
A group of parents in Florida is taking action. It's called GuardianCam.
Each time the ignition is turned on or off or the key is removed, an interior panoramic camera takes back seat pictures.
If a child is detected, the alarm goes off.
Within 15 seconds of the driver leaving the car, the windows go down and the alarm sounds. It doesn't stop until the child is removed from the car seat.
The group says it was time to stop all these avoidable deaths.
GuardianCam also works on motion detection. If a child slips into a car to play and gets locked in, the same alarms are triggered.