TYF GM

Well, they do. It's just that they aren't made of bone. They're little bits of cartilage that have yet to ossify into bone. And for more on how to know when kids are being honest, check out 50 Lies Kids Say That Parents Always Fall For.

It turns out that faking happiness can hurt your health. For a 2011 study published in the Academy of Management Journal, researchers looked at the behavior of bus drivers—a profession where people are required to have many friendly interactions throughout the day—and discovered that these people withdraw from their work while putting on a smile for show, and that that could have long-term deleterious health effects.

Over the course of a lifetime, you'll yawn approximately 250,000 times, according to one expert on the subject. If you live to 70, that's about 10 yawns per day