Childhood is not quite the stress-free paradise that our rose-tinted memories might suggest. Children -- even infants -- can suffer from chronic, toxic stress. It's stress of a very different sort than that of meetings and mortgage payments, but its long-term effects can be no less serious. Last year, the American Academy of Pediatrics launched an urgent call to action informing healthcare practitioners of the dangers of toxic stress to children. Cleary, toxic stress is serious stuff. But what is it, exactly?