Tough Enough is the second book in the Tall, Dark, and Dangerous series by M. Leighton. I read Strong Enough first and I don’t think that you would HAVE to, but I would recommend reading it first. I totally love M. Leighton's writing and I haven’t read a book of hers yet that I didn’t just absolutely love. She really draws you in with her characters and their stories. There are some twists in this book, but I won’t spoil it for anyone. I highly recommend reading this book!