These happy-go-lucky kids are a blessing and a curse when it comes to potty training. They go through the motions with a smile plastered on their face, but they also go through countless accidents with equal gregariousness. With pride, they'll yell down the hall for you that they're peeing, only for you to discover that they did it on the bathroom floor . . . with their undies still on. The benefit here is that they bounce back from setbacks, and it'd be wise if you just try to do the same.