Liz
I had the same problem with my daughter. We fought headlice for over a year. Finally, I kept her away from the little girls she babysat and that did the trick. It seems they were passing it back and forth to each other. You may need to check and see who your daughter is coming into contact with who may also have it. I also finally got trash bags and put EVERYTHING of hers in it, including everything in the closet. I also bombed my house to make sure we got all that were alive in it. These three things were what finally did the trick. Good luck!