Your 4-year-old marches around exclaiming, "I'm a stinky, poopy diaper head." She cracks herself up. You, however, are less amused.
Relax -- she's just going through a normal phase. Preschoolers, still trying to use the toilet independently, are fascinated with bodily functions, and they delight in the sound of language.
Potty talk usually disappears around age 6, but until then:
Be blasé. Ignore it as much as possible. Try not to gasp, say "Oh, no, we never say that," or punish. "Shocking you makes her feel powerful -- so the more you react, the more you may reinforce the behavior," says Debbie Glasser, Ph.D., director of family support services at Nova Southeastern University's Family Center, in Fort Lauderdale.
Set a time limit. If, despite your nonchalance, your child keeps up the bathroom humor, say, "You can talk about this for two minutes, then we're going to move on," says Barbara Polland, Ph.D., a child psychotherapist and author of No Directions on the Package. Once the time is up, introduce a new activity.
Specify what's not allowed. Explain that while she can engage in a little bit of toilet humor at home, it's not okay at preschool, a friend's house, or anywhere else in public. If she's using potty language to hurl insults, remind her that name-calling is unacceptable.
Expand her repertoire. Find some "clean" jokes to read together so she can find other topics to giggle over. Get started with Crack-Ups: A Very Silly Joke Book, by Mik Brown, and Riddles & More Riddles, by Bennett Cerf.