Hi L.,
Some Lice have become immune to some of the RID products, so it is possible that you still have a problem.
A natural and very effective method of getting rid of the problem without chemicals is:
Step 1
Saturate hair completely with Hellmann's Real Mayonnaise, Best Real Mayonnaise, or Kraft Real Mayonnaise. Be sure to work the mayonnaise in the hair and roots well. Hair MUST be extremely greasy from the mayonnaise to prevent lice from breathing.
Step 2
Wrap hair as tightly as possible with Saran Wrap or Handi-Wrap (or a shower cap), then wrap with a towel.
Step 3
Allow to remain on head for at least one hour. Two hours will guarantee all the lice are dead. (in really heavy infestations, I have had families leave the wrapped hair over night) During this time take all pillow cases, towels, blankets, sheets and clothes that have come into contact with any lice-infested hair and run them through the washing machine and dryer.
Step 4
Shampoo hair thoroughly. Rinse hair with Heinz White Vinegar, then rinse clean with water. Comb hair with a nit comb if desired. No nits should survive this treatment if done properly.Congratulations! You're done! There's no need to repeat the treatment in seven days as with medicated shampoos. Don't worry about any lice that may have escaped during the treatment. Lice die within 12 to 24 hours without a human head to feed on and, contrary to popular belief, they cannot jump nor will they transfer to your pets.
TeaTree shampoos (available thru health food stores and sometimes at salons) will help prevent future infestations.
You may also want to vacuum and or spray down any upholstered furniture and bag up your daughter's stuffed animals etc. Soak headbands, combs, brushes and hats in a Rid solution or bag them in a tightly sealed trash bag for 12-24 hours. Lice need a human host to live, but can survive for some time on cloth covered items...so you will need to do whatever is necessary to make sure that the rest of the family is not infected.
Hope this is helpful!
V. R