 their temperature climbs almost like three to five times faster and they lose sweat slower. Since temperatures can rise nearly 20 degrees within the first 10 minutes inside a vehicle, she also says if you see a child alone inside a car, do not hesitate to call 911 as taking that action could save a life. Dr. Grover says it's imperative to never leave the car without checking the backseat. She also recommends you keep an important item like your phone or bag next to your child so you won't forget to look when you get to your destination.