In this week’s Keeping Kids Healthy column by UTMB Drs. Sally Robinson and Keith Bly: On an especially hot day, the interior of a car can heat up to 122 degrees in less than 20 minutes; within 40 minutes, it can get so hot that a child left inside a car for that length of time can die. Many parents think that leaving the window of the car open slightly will keep the temperature lower, but fail to realize that it will still remain too hot in the car for the child.