He's known to the world for his bestselling historical non-fiction and his familial tie to Princess Diana, but Earl Charles Spencer is now revealing a far more side of his life. In his new memoir, "A Very Private School," Spencer recounts the years of brutal abuse and culture of cruelty he encountered while growing up in boarding school -- drawing on his memories as well as letters and diaries from his childhood.Earl Spencer explains why he believed he needed to write this book despite having to relive the emotional trauma, what his relationship was like with his older sister, Princess Diana, growing up, and how he believes the abusers who worked at his school should be held accountable.Follow Martha on Twitter: @MarthaMacCallumLearn more about your ad choices. Visit megaphone.fm/adchoices