Inside the Moment We Told Bette Davis That Her Daughter Had Written a Scathing Tell-All About Her

Bette Davis’s longtime personal assistant was suspicious when she heard the star’s eldest daughter was writing a memoir.

“I know they loved each other but there was a lot of history there,” says Kathryn Sermak, 61, who is featured in the current issue of PEOPLE.

Sermak — who served as a live-in assistant to Davis off and on during the decade leading up to the Hollywood legend’s death in 1989 — says she called Davis’s daughter Barbara (nicknamed Bede) in 1985 to dissuade her from publishing the book.

She recounts the phone call in her own memoir, Miss D and Me: Life with the Invincible Bette Davis, which is excerpted exclusively in PEOPLE.

” ‘Please don’t publish this book. If your mother finds out you did this behind her back, the shock might kill her,’ ” Sermak writes of the conversation. “[But] Bede explained that the publication date was set, and she intended to surprise her mother with it on Mother’s Day. If we told her before then, any harm that came to Miss D would be our responsibility, not hers. She insisted it was a book that her mother would grow to love.”

• For more from Sermak — including how Davis reacted to the scathing tell-all that was written by the star’s daughter — pick up the latest issue of PEOPLE, on newsstands Friday

As the publication date of Bede’s book, My Mother’s Keeper, approached, Sermak and Davis’s lawyer Harold Schiff knew they had to tell the star, then in her late 70s, of it’s existence.

” ‘What? My Bede has written a book about me? Impossible, she would never do that…. How long have you known about this?’ ” Sermak writes of the conversation with her boss, who had become a bit of a surrogate mother to her over the years. “Harold told her. She looked at me. I was crying. ‘How could you not have told me?,’ Miss D cried. ‘To have both my beloved daughters betray me!’ ”

The book turned out to be a scathing tell-all that painted Davis as an overbearing alcoholic who was abusive to her grandchildren. Bede’s step-father Gary Merrill publicly denounced the memoir; Davis wouldn’t speak about it. She never forgave Bede.

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Mother and daughter remained estranged through 1989, when Davis was told her breast cancer, in remission for five years, had “exploded,” and she had just days to live.

“Miss D accepted it,” Sermak writes of hearing the prognosis. “She told me to call her son Michael and then Harold. She did not ask me to reach out to Bede.”

It was Sermak who was holding Davis’s hand when she died on Oct. 6 of that year at the age of 81.

Miss D and Me: Life with the Invincible Bette Davis is available Sept. 12.