I feel that this book wasn't as great as the percy series. It still has the humor, and excitement as percy, but still I felt that it was much too long. Sadie is the comedian in this one, and Carter is the annoying older brother, but you still can't feel sorry for him. Sadie and Carter have that great brother- sister chemistry that just makes you smile. Their are fun fight scenes, and funny characters. Another reason why this makes this book shine is the charm of Basta, the Godess of cats. She loves Friskie, and is a amazing fighter. I wouldn't be too worried about any inappropriate content. There is no sex, or kisses, just small cute flirting. The swearing includes bloody, it's British, and as long as your child knows not to say it in school, they should be find. The violence includes a creepy villain Set. There are battles with monsters with funny conclusions. Younger readers might be disturbed dying because of the father's mistake, and that the parents lied to them only because they had to protect them. As long as your child knows that you wouldn't lie to them they should be good to go. Any older readers won't have a problem with it. Now why I gave it three stars. I felt that it was overlong by 100 or so pages, in you know what I mean. I also didn't like that it felt too rushed, as if the author was trying to hard to make it funny, and charming like his Percy series. Because of this, it loses the charm that I really enjoyed about percy. Thank you, and enjoy!