LOS ANGELES (CBSLA.com) — Francesca Hilton, the only daughter of actress Zsa Zsa Gabor and Hilton Hotels founder Conrad Hilton, has died of an apparent stroke/heart attack, her publicist said Tuesday. She was 67.

Constance Francesca Gabor Hilton died at approximately 10:20 p.m. Monday at Cedars-Sinai Medical Center, publicist Edward Lozzi said. She was with her fiancé, Michael Natsis, who administered CPR before paramedics arrived, Lozzi said.

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“As Francesca’s publicist and one of her best friends I am shocked,” Lozzi said. “We were on the phone minutes before she died. We were discussing her book she was writing and a possible deal. She had to go to the restroom. She never made it out.”

Hilton had been embroiled in a long feud with her mother’s ninth husband, Frederic Prinz von Anhalt, over his guardianship of his 97-year-old wife and the expenses incurred in looking after her.

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Hilton called her attorney Ken Kossoff just hours before her death, asking that he take action against von Anhalt for allegedly violating a court order, allowing her to visit her mother, Lozzi said.

Hilton is a great aunt of socialite Paris Hilton.

Funeral arrangements are pending, Lozzi said.

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