We dealt with this issue twice, and both times, used a nit comb ( https://www.treat-lice.com/wp-content/uploads/2015/11/met... ) after adding a mixture of coconut oil and apple cider vinegar, which we made into a paste, into the hair. A shower cap was left on for a few hours with the mixture, and we repeated it a few times. Bedding and stuffed animals were washed in hot water (stuffed animals left in plastic bags for a few weeks). The second time the kiddo caught lice, a year later, family members and I first used an electric nit comb, then applied that same mixture, let it sit for a few hours with a shower cap, and followed through with a daily combing with the nit comb after shampooing the hair daily with a tea tree oil shampoo. The mixture was recommended to me by my daughter's aunt, who knows a hair stylist who has dealt with lice with her own two kids.
As a preventative measure, I spray her hair with this product ( http://www.tinyoranges.com/wp-content/uploads/2013/03/Fai... ), which repels lice. They also have a lice and nit treatment shampoo apparently, which I was unaware of ( https://s-media-cache-ak0.pinimg.com/564x/75/e7/e4/75e7e4... ), and combats lice and the nits. It is made with natural ingredients, has no pesticides, and is safe. It's probably pricey as the repelling spray is pricey, in the $15-$20 range but I think it is worth it considering the aggravation, trouble and stress that the thought of lice can cause someone. By the way, her aunt took her to get a hair cut, which helped with the tangling issues, and made combing through with the lice comb much easier. Cutting hair won't prevent lice, but it will make it easier to treat and deal with lice. Her hair is past the shoulder now, whereas before it was almost to her waist. Make sure to teach your daughter not to share hats, hair brushes, hair clips, and anything that goes on the head. The kids in her aftercare liked braiding her hair, and I wouldn't be surprised if the scrungy they would use to keep her braid intact had been used by someone in her class that had lice.