Rachel Vail is the author of children's books including Sometimes I'm Bombaloo and Righty and Lefty, in which she also collaborated with artist Matthew Cordell. She is also the author of several books for teens and middle grade readers, including If We Kiss, You Maybe, Gorgeous, Wonder, and Never Mind, which she wrote with Avi. Vail attended Georgetown University, where she earned her B.A. in English and Theater. She lives in New York City with her husband and two sons.
Matthew Cordell is the Caldecott award-winning author and illustrator of Wolf in the Snow, Trouble Gum, Another Brother, hello! hello!, and Wish. He has illustrated numerous books by renowned authors including Philip Stead (Special Delivery), Rachel Vail (the Justin Case series), and Gail Carson Levine (Forgive Me, I Meant to Do It: False Apology Poems). He lives with his family in Gurnee, Illinois.