I am a pediatrician. I think I understand why this book works so good: honesty it is like children magic. The author knows kids and has created a story with animations and dialogue at a very appropriate level for their understanding. My boy was very interested in this story. We used the app anytime he would sit there, even underwear . He loved it. Prepare yourself people to read this text over and over. This story helped him slow down and wait and created a consistent dialogue for us to use as