Jaime Mann Hi Daniel! The target age range is Middle Grade, so roughly 9-12. It's so hard to say what an individual child might think about any book! I've had excellent feedback from children in the 11-12 age range. I've also had good reviews from teens and adults, saying they can't wait for the next installment. My advice would be to have the 11 year old read it and see if she recommends it for the 13 year old. Thank you so much for your interest!