Singer Natalie Cole, the daughter of Nat King Cole, has died at the age of 65.
The TMZ celebrity news website said Cole died from congestive heart failure following complications from a kidney transplant and Hepatitis C, diagnosed in 2008.
Cole scored a big hit in 1991 with Unforgettable - a virtual duet with her late father, who died before his daughter began her solo career.
The Grammy-winning singer died on Thursday night at a hospital in Los Angeles, her publicist told the Associated Press news agency.
She rose to fame as an R&B artist with tracks such as This Will Be and Inseparable.
The singer recently had cancelled a series of performances, including one on New Year's Eve.
"Natalie fought a fierce, courageous battle, dying how she lived... with dignity, strength and honour. Our beloved mother and sister will be greatly missed and remain unforgettable in our hearts forever,'' said a statement from her son Robert Yancy, and sisters, Timolin and Casey Cole, AP reported.
The singer had battled drug problems and hepatitis in the past, and underwent a kidney transplant in 2009.
Cole broke out in 1975 with the hit This Will Be which won the Grammy for best R&B female performance and also earned her the Grammy for best new artist.
Her career reached the superstar level in 1991 when she recorded Unforgettable ... With Love, an album of songs related to her father, the silky-voiced singer who was one of the most popular performers of the 1940s and '50s but died before his daughter began her solo career.
Using technology that was cutting edge at the time, studio engineers merged her voice with her father's in the song Unforgettable, which had been a hit for Nat King Cole in 1951. The result was a moving, sentimental No. 1 hit 40 years later, that actually sounded as if the two were singing a duet.
The album included reworked versions of some of her father's best-known songs, including That Sunday That Summer, Too Young and Mona Lisa.
The song Unforgettable and the album it came from earned Cole three Grammy Awards.
"I thank my dad for leaving me such a wonderful, wonderful heritage," Cole said in accepting her awards.
In all, she won nine Grammys.
The daughter of crooner Cole and jazz singer Maria Hawkins - who worked with Duke Ellington - Natalie grew up surrounded by music in an affluent neighbourhood of Los Angeles.
Her father died from lung cancer when she was only 15, and she struggled to come to terms with his death. However, she appeared to find solace in music.
She began performing in college and had early success with her debut album Inseparable in 1975. The album track This Will Be became a top ten hit and went on to win Cole a Grammy for best female R&B performance.
Cole was also named best new artist at the Grammys - and the album's title track, Inseparable, became another chart hit.
The follow-up albums Natalie and Unpredictable cemented her success, with tracks such as Sophisticated Lady and I've Got Love On My Mind bringing further chart glory.
In 1977, she had two platinum albums and her own Christmas special - and two years later she received a star on the Hollywood Walk of Fame.
But her drug problems came to prominence in the 1980s and there followed a predictable slump in her career, as she battled addiction.
She re-emerged on the music scene in 1987, signed to a new label and with a new sound. Jump Start (My Heart) and her cover of Bruce Springsteen's Pink Cadillac were among her notable pop hits, while 1989's Miss You Like Crazy won her international acclaim.
She returned to the classic standards associated with her father in the 1990s, telling the Associated Press, she had to "throw out every R&B lick that I had ever learned and every pop trick I had ever learned".
"I didn't shed really any real tears until the album was over,'" Cole said. "Then I cried a whole lot.
"When we started the project, it was a way of reconnecting with my dad. Then when we did the last song, I had to say goodbye again."
In 2008, 17 years after Unforgettable... with Love, Cole released Still Unforgettable, which included not only songs made famous by her father but other artists, including Frank Sinatra.
The same year, she was diagnosed with Hepatitis C - which she believed was the result of her intravenous drug use in the early years of her fame.
Her battle with drugs, including heroin and crack cocaine, was charted in her 2000 autobiography Angel on my Shoulder.
She underwent a successful kidney transplant in 2009 - after being inundated with offers of kidneys from fans - and continued to tour and make public appearances on TV shows, including American Idol.
"I am a walking testimony to you can have scars,'' she told People magazine. `"You can go through turbulent times and still have victory in your life.''
Cole was married three times, and had one son.