About uv light. if your kids are going to wear clothes, keep them dry. if they get wet, they still need the sunblock. >> do you need to put the sunblock on underneath the clothes? >> sure. make sure you apply 15 minutes before you go outdoors and if you wear the outer garment and it stays dry, you're very well protected. if they're in and out of the water, make sure they take a break every half hour or so. if you don't use the sunblock, a wet t-shirt is like wearing nothing at all. >> how early do we need to be starting this with kids? infants, you worry about putting certain lotions on them, ...