In a message to fans on Lee's Website, daughter Nicki Lee Foster said the Grammy-winning singer-composer died at about 8 p.m. The cause of death appears to have been from a myocardial infarction, the result of a stroke she suffered three years ago.
"My children David, Holly, and Michael and I were comforted by the fact that she was at home, and that I was able to be by her side," she said. "My mother was always very appreciative of the love and loyalty she received from her wonderful fans, and so this is the first announcement to be made."
With her soft, come-hither vocal style, Lee crooned her way through a career spanning five decades, recording songs for the Benny Goodman band, writing for Disney's hit film Lady and the Tramp and earning both a Grammy and an Oscar nomination.
Yet amid all of her success, Lee, who was a diabetic, suffered from a number of health problems as far back as the 1950s. She came down with a severe case of pneumonia in 1961. Fifteen years later, she nearly died in a fall in her New York hotel room, and she took another near-fatal fall in Las Vegas in 1987. She also had two major surgeries in 1985--one to clear blocked arteries, the second a double-bypass--which left her confined to a wheelchair since the early '90s.
Lee was born Norma Deloris Egstrom on May 26, 1920 in Jamestown, North Dakota, the seventh of eight children. After years of singing in church choir and her high school glee club, she headed for Hollywood in 1938. Three years later, she was fronting Benny Goodman's band after he spotted her during a performance at a Chicago hotel. Lee toured the U.S. with Goodman in a two-year stint that brought such hits as "Why Don't You Do Right" and "Elmer's Tune"
She eventually married Goodman's guitarist, Dave Barbour, and Lee began recording for Capitol Records collaborating with her husband on hits like "Fever," "Mañana" (the most popular song of 1948), "You Was Right, Baby" and "It's a Good Day."
Lee's marriage to Barbour soon fell apart under the strain of his alcoholism, and they divorced in 1952. Aside from Barbour, Lee also was married to actors Brad Dexter and Dewey Martin, and percussionist Jack Del Rio.
Her greatest success, meanwhile, came in the 1950s, from albums such as Black Coffee and Beauty and the Beat, and she picked up a Grammy for her 1969 hit, "Is That All There Is?"
From there, Lee moved into a new direction, eventually making her way to the big screen. Lee sang the title track to Johnny Guitar, she was nominated for a Best Supporting Actress Oscar for Pete Kelly's Blues and had a featured role opposite Danny Thomas in 1953's update of The Jazz Singer.
Some of her most memorable big-screen work came from Disney's Lady and the Tramp. Lee lent her voice to the roles of Peg and the Siamese cats, and she cowrote six songs for the film including "He's a Tramp (But I Love Him)." She later sued Disney over profits from the sale of the home video, and a California court awarded her $2.3 million.
In 1984, Lee took her life to Broadway, appearing in the short-lived autobiographical show "Peg."
Lee is survived by her grandchildren David Foster, Holly Foster-Wells and Michael Foster, and by her great-grandchildren Teagan Foster, Caleb Foster and Carter Wells.