Kicking Her Legs

It could mean: She's having a swell time. When your baby spies something amazing -- like water pouring from the bathtub spout -- leg banging is her way of saying "Wow!"

How to respond: Share her enthusiasm: Kicking her legs helps her develop the muscles she needs to crawl. So if the neighbor's dog gets your baby kicking, arrange a puppy playdate. Along with any body language, experts say to always watch your baby's face: That'll help you sort out what she's thinking.

Or it could mean: She wants a little face time. Your baby probably figured out that banging her legs against the crib mattress not only makes a pleasingly loud thump, it also often attracts her favorite person: you.

How to respond: Set her on your lap and sing "The Wheels on the Bus." Kicking perfectly accompanies the up-and-down rhythm of the song, and she's in the right position to get plenty of one-on-one time with Mom or Dad.