Joe and Rose Kennedy's strikingly beautiful daughter Rosemary attended exclusive schools, was presented as a debutante to the Queen of England, and traveled the world with her high-spirited sisters. And yet, Rosemary was intellectually disabled -- a secret fiercely guarded by her powerful and glamorous family. Rose Kennedy's diaries and correspondence, school and doctors' letters, and exclusive family interviews bring Rosemary alive as a girl adored but left far behind by her competitive siblings. Kate Larson reveals both the sensitive care Rose and Joe gave to Rosemary and then -- as the family's standing reached an apex -- the often desperate and duplicitous arrangements the Kennedys made to keep her away from home as she became increasingly intractable in her early twenties. Finally, Larson illuminates Joe's decision to have Rosemary lobotomized at age twenty-three, and the family's complicity in keeping the secret. 'Rosemary' delivers a moving coda: JFK visited Rosemary for the first time while campaigning in the Midwest. She had been living isolated in a Wisconsin institution for nearly twenty years. Only then did the siblings understand what had happened to Rosemary and bring her home for loving family visits. It was a reckoning that inspired them to direct attention to the plight of the disabled, transforming the lives of millions.

She made John Lennon blush and Marlon Brando clam up. She cold-shouldered Princess Diana and humiliated Elizabeth Taylor. Andy Warhol photographed her. Jack Nicholson offered her cocaine. Gore Vidal revered her. John Fowles hoped to keep her as his sex-slave. Dudley Moore propositioned her. Francis Bacon heckled her. Peter Sellers was in love with her. For Pablo Picasso, she was the object of sexual fantasy. "If they knew what I had done in my dreams with your royal ladies" he confided to a friend, "they would take me to the Tower of London and chop off my head!" Princess Margaret aroused passion and indignation in equal measures. To her friends, she was witty and regal. To her enemies, she was rude and demanding. In her 1950's heyday, she was seen as one of the most glamorous and desirable women in the world. By the time of her death, she had come to personify disappointment. One friend said he had never known an unhappier woman. The tale of Princess Margaret is pantomime as tragedy, and tragedy as pantomime. It is Cinderella in reverse: hope dashed, happiness mislaid, life mishandled. Combining interviews, parodies, dreams, parallel lives, diaries, announcements, lists, catalogues and essays, Ma'am Darling is a kaleidoscopic experiment in biography, and a witty meditation on fame and art, snobbery and deference, bohemia and high society.