16-year-old Skylar Neese was murdered by her two best friends in 2012, supposedly because of an argument over social media. What actually led these high school girls to commit such a violent act on a friend? We talk with podcaster and true crime writer M. William Phelps, host of 'Paper Ghosts' and author of books including ‘We Thought We Knew You’ and ‘Don’t Tell A Soul.'