Now! For years we've heard babies younger than 6 months shouldn't wear sunscreen: they should just be kept out of the sun. Which is, of course, unrealistic. The AAP recently changed that stance and now recommends sunscreen for tots of all ages as there hasn't been any evidence of negative long-term effects on infants younger than 6 months using it. Look for a baby formulation that has the words "broad spectrum" on the label, meaning it protects from UVA and UVB rays. And remember that sunscreen isn't a license to keep your baby on the beach for hours on end. Put a sunhat on her, seek shade, and use common sense.