Sister Sledge is an American musical group from Philadelphia, Pennsylvania, formed in 1972 and consisting of four sisters: Kim Sledge (born 21 August 1958), Debbie Sledge (born 9 July 1954), Joni Sledge (born 13 September 1957), and Kathy Sledge (born 6 January 1959). They also have an older sister, Carol, who is not a musical celebrity.
All the sisters are granddaughters of the former opera singer Viola Williams. The sisters used to perform under the name of 'Mrs. Williams Grandchildren'.
