BTW hair dye that has an ammonia base will kill the lice and dissolve the glue that holds the nits onto the hair shaft. Don't change the kids hair color just use the same shade. It is way safer than using the stuff you buy from the pharmacist. That is a nerve poison. There are cumulative effects (i.e. the more you use it the more it will affect you). I have used the hair dye and can vouch for it's effectiveness. You must get the type that uses ammonia. It is the ammonia that is doing the killing.