Finding a lice infestation in your child's hair can cause panic. Lice are tiny gray insects that feed on your child's blood and can easily be spread to and from other children at school or daycare. Pediatrician Dr. Cindy Gellner says the good news is the infection can be treated with over-the-counter lice shampoo. If you suspect your child has lice, learn some tips to contain and prevent the infestation.