Thank-you for your question.
From the evidence I have been able to collect Ava Gardner died of
pneumonia in London (UK) on January 25, 1990.
"After a stroke in 1989, which left her partially paralyzed and
bedridden, Frank Sinatra paid her medical expenses. She died of
pneumonia in London, England at the age of 67 in 1990."
"Ava's last public appearance in North Carolina was in 1978 at the
Rock Ridge High School reunion, with North Carolina's Governor James
B. Hunt, who is also a Rock Ridge High graduate. Her last visit in
Smithfield was in May 1985. In 1986, she suffered a stroke, and she
died of pneumonia on January 25, 1990. She is buried in Sunset
Memorial Park, Highway 70, in Smithfield."
"Cause of death: Pneumonia"
"She died of pneumonia in London, England."
"Ava Gardner (actress) -- Dead. Pneumonia. Died January 25, 1990. Born
December 24, 1922. An ex-wife of Frank Sinatra and Mickey Rooney."
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