This is one time that spitting should be encouraged! At around 5 months, your child will start blowing spit bubbles  -- or raspberries  -- a skill that helps her learn how to move her mouth, tongue, and lips together, and later be able to form words, says William Lawrence, Jr., M.D., former medical director at Children's National Medical Center in Washington, DC.

So laugh it up whenever she makes raspberries  -- even better, do it with her. In no time, she'll be telling you just how funny you are!