B.K.
Been there done that. The only thing that really works is getting rid of all the nits after you've killed the live lice with the treatments. (I have used Rid, and also after that didn't work twice, I ordered a chemical-free shampoo from www.Qbased.com. It's Q-based healthcare. It worked better for us than the Rid, but it takes a few days for it to arrive.)
Anyhow, you need to make sure that after you do the treatment, you spend every night for several days going through the hair for nits and picking them out and throwing them away. (The combs don't work as they are too big. You actually have to pull the nit off the hair shaft. It's very time consuming and tiring.) Nits aren't killed by the shampoo. Get your glasses out and use a desk light right by your daughter's head to really see what you're doing. They are very hard to see. Also, every day that you find nits, you need to wash your daughter's bedding in HOT water. And you need to get a spray (chemical or not) and spray your furniture. Nits and lice can live on bedding and furniture. Also, did you bag up all her stuffed animals in plastic bags? You need to do that, and let them sit for a month. (they say two weeks but do a month) Nits hatch and look for a live body. If they are on the stuffed animals and they hatch and don't find a human, they will die. That's why they tell you to bag the stuffed animals, and anything else in her room that could have a nit on it. (dolls, soft toys, etc.)
Anyhow, you could try the olive oil and mayo or other things like that, but in the end it's getting rid of all the nits in her hair and in your house that actually gets rid of the problem. It's a pain isn't it!!!?? I have two daughters and we've been through lice three times in their lives (one is 20, the other is 10). E-mail me if you have questions. I feel for you! We just went through this a year ago when they went through our school.
Bobbi