Singer Bonnie Pointer, best known as a member of the Grammy-winning group The Pointer Sisters, has died at the age of 69.
She died on Monday, according to her sister and fellow singer Anita.
No cause of death was revealed.
In a statement to the PA news agency, Anita said: "It is with great sadness that I have to announce to the fans of The Pointer Sisters that my sister, Bonnie, died this morning.
"Our family is devastated, on behalf of my siblings and I and the entire Pointer family, we ask for your prayers at this time."
The Pointer Sisters – at different times including Bonnie, Anita and their siblings June and Ruth – formed in Oakland, California, and first found success in the 1970s.
Their best-known songs include Jump (For My Love) and I'm So Excited.
The group won three Grammy awards and were honoured with a star on the Hollywood Walk of Fame in 1994.
Bonnie left the group in 1977 and pursued a solo career. Heaven Must Have Sent You is perhaps her biggest hit.
Anita, 72, added: "Bonnie was my best friend and we talked every day, we never had a fight in our life, I already miss her and I will see her again one day.
"The Pointer Sisters would never have happened had it not been for Bonnie."
Bonnie is survived by her brothers Aaron and Fritz, as well as sisters Ruth and Anita Pointer, a representative said.
June died in 2006. Bonnie and Anita recently released a tribute song titled Feels Like June, which was Bonnie's final recording.
The Pointer Sisters currently consists of Ruth, her daughter Issa Pointer and her granddaughter Sadako Pointer.