Last year 32 children across the nation died when they were left in a locked car on a hot day. In many cases parents simply forgot to take the child with them.
Officials in Houston went to an extreme to remind parents of the danger. They've put electronic signs all over town, showing the temperatures both outside and inside a car. It can be at least 15 degrees hotter inside and children are far more sensitive to heat than adults.
"We've heard of cases where kids have been in cars for less than an hour, maybe 30 minutes and by the time we get there they are already very, very sick and the tragedy sometimes is that they have already stopped breathing," said David Persse from the Houston Fire Department.
Officials recommend parents leave a handbag or briefcase in the back seat to remind them to take their child out of the car.