Shirley Ardell Mason was born on 25 January 1923. Her mother was well-known for being “bizarre”, with a “witch-like” screeching laugh, and would often walk around in the dark, looking into neighbours’ windows. She was later diagnosed with Schizophrenia. By the 1950s, Shirley had long been suffering from long periods of blackouts and emotional breakdowns. Eventually, she went to a psychiatrist named Cornelia Wilbur, who determined that Shirley was suffering from Multiple Personality Disorder (now known as Dissociative Identity Disorder). Wilbur’s sessions with Shirley were the inspiration of the book (and later movie) Sybil by Flora Rheta Schreiber, who changed Shirley’s name to Sybil Isabel Dorsett to protect Shirley’s identity.
Years after the book and movie of Shirley’s life was released, experts began to pick apart the story and find things that just didn’t add up. For one, the book stated that “Sybil” had 16 different personalities. The book was not written in the style of a case study, but rather as a novel. Experts who interviewed Wilbur concluded that she had suggested MPD to Shirley, whom they thought of as simply a “suggestible hysteric”.
In 2011, Debbie Nathan published a book titled Sybil Exposed, which documents what the author believes to be evidence that Wilbur, Shirley, and Flora made up the content of the book. She shows a letter that Shirley wrote in 1958 where she admits openly that she faked the “Multiples” for attention.
Cornelia Wilbur passed away in 1992. Shirley Mason was diagnosed with breast cancer in 1990, and the following year Parkinson’s Disease. She passed away on 26 February 1998.