Best of luck with your book :) The first book I've read that really resonated with me about giving life to characters is The Screenwriter's Bible by David Trot

Best of luck with your book :) The first book I've read that really resonated with me about giving life to characters is The Screenwriter's Bible by David Trottier. BTW, I've read a lot more books about screenwriting than about writing novels, but I believe both apply... stories are stories.