Annie's Ghosts: A Journey into a Family Secret - Steve Luxenberg

Beth Luxenberg was an only child. Or so everyone thought. Six months after Beth's death, her secret emerged. It had a name: Annie.
Steve Luxenberg's mother always told people she was an only child. It was a fact that he'd grown up with, along with the information that some of his relatives were Holocaust survivors. However, when his mother was dying, she casually mentioned that she had had a sister she'd barely known, who early in life had been put into a mental institution. Luxenberg began his researches after his mother's death, discovering the startling fact that his mother had grown up in the same house with this sister, Annie, until her parents sent Annie away to the local psychiatric hospital at the age of 23.
Annie would spend the rest of her life shut away in a mental institution, while the family erased any hints that she had ever existed. Through interviews and investigative journalism, Luxenberg teases out her story from the web of shame and half-truths that had hidden it. He also explores the social history of institutions such as Eloise in Detroit, where Annie lived, and the fact that in this era (the 40s and 50s), locking up a troubled relative who suffered from depression or other treatable problems was much more common than anyone realizes today.