Everyone has something is a good book about PKU specifically. Each page depects a different person with a different challenge in their life (wheel chair, glasses, etc.). Virginia Schuett also has a children's book about PKU that is a nice intro about why a child is on a special diet. There is also one called Herb the Vegetarian Dragon which we always had the teacher read at some point in the year. It is about a dragon who is very gentle and has a garden. His fellow carnivorous dragons are annoyed that he will not pillage and eat the villagers and the villagers capture Herb thinking he is a man-eating dragon. It goes more into the philosophy of everyone belonging and how people should not be pressured to eat what everyone else is eating.