Children's physiology makes them different from adults. They heat up faster, and cannot sweat as much. Normally, this isn't a problem. But hot, humid weather puts them at higher risk of heat exhaustion and the more dangerous heat stroke. Though the two are related, heat exhaustion is different from heat stroke.
Heat exhaustion takes time to develop, while heat stroke can strike suddenly.
While first aid is appropriate for both conditions, heat stroke is an emergency requiring hospital care. Drinking water is still a good idea, as long as kids remember to drink what they need to replace lost fluids. In addition, doctors recommend gradual exercise while getting used to a hotter, more humid climate, and stress the importance of single-layer, lightweight, absorbent clothing. Sweat-saturated garments should be changed to dry ones. CNN Correspondent Brian Cabell contributed to this report.