Joan Elise Sledge (September 13, 1956 – March 10, 2017)^[4] was an American singer best known as a founding member of the family vocal group Sister Sledge. The group was known for their hits during the mid-1970s through the mid-1990s; most notably 1979's "We Are Family" and "He's the Greatest Dancer".^[5][6]

Sledge was born the third of five daughters in Philadelphia, Pennsylvania, to Edwin Sledge, a tap dancer, and his actress wife, Florez (née Williams).^[6] Described as a warm extrovert, Sledge attended Olney High School, graduating in 1974. Sledge majored in communications while in college and began acting in school productions at Temple University.^[1][7][8] During her sophomore year at Temple, she directed her first stage-play "Wild Flower", written by Hazel Bright and produced by Ron Alexander.^[9]

In 1971, Sledge and her sisters formed the musical group Sister Sledge and released their debut single "Time Will Tell". In 1975, they released their first album Circle of Love. On their third album We Are Family (1979), Sledge sang lead vocals on the single "Lost in Music". In 1980, she performed lead vocals on their "Reach Your Peak" for their album Love Somebody Today. In 1981, Joni began sharing lead vocals with her sister Kathy Sledge within the group. Following the departure of Kathy Sledge in 1989, Joni performed as the lead vocalist of the group.

In 1996, Sledge wrote the song "Brother, Brother Stop" after witnessing a shooting incident in Los Angeles. The song was featured on Sister Sledge's greatest hits collection. She also wrote and produced their album African Eyes (1997).

Sometime during her career, Sledge briefly lived in Paris, France and studied at Sorbonne University.

In addition to singing, Sledge was also a songwriter and producer; writing and producing the song "Brother, Brother Stop" for a Sister Sledge greatest hits album in 1996. Sledge's production of their album African Eyes which was released in 1997 was nominated for a best-production Grammy.^[6]

Sledge had a son named Thaddeus Everett Whyte IV from her marriage to Thaddeus E. Whyte III which was from 1992 until 2000.^[9] Sometime during her career, Sledge briefly lived in Paris, France and studied at Sorbonne University.^[9]

Sledge, at age 60, was found dead by a friend at her home on March 11, 2017, in Phoenix, Arizona.^[10] Her death was originally attributed to unknown circumstances as she had no known illnesses, according to close family sources.^[11] On March 14, 2017, Sledge's cause of death was ruled "natural causes" related to a pre-existing condition.^[12][13][14]