Constance Francesca Gabor Hilton, 67, died Monday night in Los Angeles.
Hilton, the only daughter of Hilton Hotel founderConrad Hilton, who died in 1979, and Zsa Zsa Gabor, 97, died of an "apparent stroke/heart attack," says her rep, Edward Lozzi.
She was with her fiancé Michael Natsis who administered CPR with paramedics before she was rushed to Cedars-Sinai and pronounced dead, says Lozzi, who adds that Hilton passed away at around 10:20 p.m. Monday.
"As Francesca's publicist and one of her best friends I am shocked. We were on the phone minutes before she died," says Lozzi. "We were discussing her book she was writing and a possible deal. She had to go to the restroom. She never made it out. I am so sad about my friend ..."
Hilton had battled her stepfather, Frederic von Anhalt, in court over mom Zsa Zsa's finances and care for years.
According to Lozzi, von Anhalt defied a court order this month and told Hilton she would no longer be allowed in the house to see her long-ailing mother, who is suffering from dementia and cannot speak.
Hilton had called her attorney Ken Kossoff in Los Angeles hours before she died to plot a course of action.
Francesca Hilton at one time dated actor Peter Sellers and worked as a professional photographer, actress, comedian and as a publicist for artists in the 1980s. She is a great aunt of Paris Hilton.
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