Reading takes practice. If she is having trouble with sight words, it would be helpful to use flashcards of words that you see that she is having difficulty with. You can make it into a game where she gets to keep the flashcards that she gets right for the day. Depending on how much trouble you want to go to, you might even make her a bulleting board to pin her flashcards on. I would personally do 10 cards at a time (assuming she is a younger child) and reward her by letting her stay up past her bed time one minute for every card she got that day. The next day, you add those cards back to your stack, so she can learn to retain the words permanently. You sound like an amazing mom who is really concerned about your daughter, and that means that she has half the battle won already! Let me know how it turns out for you.