Sister Sledge is an American musical group from Philadelphia, Pennsylvania. Formed in 1971, the group consisted of sisters Debbie, Joni, Kim and Kathy Sledge. 1979 saw the release of their breakthrough album We Are Family, which peaked at number three on the US Album Chart and went Platinum. With Kathy leaving in 1989, the group have since operated as a trio (with Kathy occasionally re-joining for one-off performances and several releases in the 1990s). Symbolizing strong family values, the siblings achieved international success at the height of the disco era.
Sister Sledge's 1979 single "We Are Family" reached number two on the US Billboard Hot 100 and earned them a Grammy Award nomination. Their other US hits include a 1982 cover of "My Guy". The group had UK Top 20 hits with "Mama Never Told Me", (1975), "He's the Greatest Dancer" (1979), "We Are Family" (1979), "Lost in Music" (1979), and "Thinking of You" (1984), before reaching number one on the UK Singles Chart with the song "Frankie" in 1985. Remixed versions of three of their singles in 1993 returned them to the UK Top 20. In 2015, Sister Sledge performed for Pope Francis at the World Festival of Families in Philadelphia.