Phantom Stallion, 18: Firefly

Terri Farley​ is the best-selling author of books about the contemporary and historic West. Her most recent book ​Wild at Heart: Mustangs and the Young People Fighting to Save Them​ (Houghton Mifflin Harcourt) is a Junior Library Guild selection; winner of the Sterling North Heritage award for Excellence in Children's Literature; and has been honored by Western Writers of America, National Science Teachers Association, and American Association for the Advancement of Science. She is a recent inductee into the Nevada Writers Hall of Fame. Her ​Phantom Stallion​ (HarperCollins) series for young readers has sold over two million copies worldwide.