Sister Sledge is an American musical group from Philadelphia, Pennsylvania, formed in 1971 and consisted of four sisters: Debbie Sledge (born July 9, 1954), Joni Sledge (born September 13, 1956), Kim Sledge (born August 21, 1957), and Kathy Sledge (born January 6, 1958).

They are granddaughters of the former opera singer Viola Williams. The group is best known for their hit songs "We Are Family", "Lost In Music", "He's the Greatest Dancer", and "Frankie".The members of Sister Sledge were born and raised in Philadelphia and began singing in local Philadelphia churches like Williams Temple CME and Second Macedonia Baptist Church.

Their professional music career launched when they entered the UK Singles Chart in 1975 with "Mama Never Told Me". The young girl group released their first two albums, Circle of Love and Together in 1975 and 1977, respectively but, aside from scoring the Silver Prize at the 1975 Tokyo Musical for Gwen Guthrie's composition "Pain Reliever" and oft-recorded "Love Don't You Go Through No Changes on Me," Produced by Bert Deco and Tom Bell.

The group attained pop success with their next album: 1979's We Are Family. The album would become the group's best selling. Singles included "He's the Greatest Dancer" (#9 US, #1 R&B) and "We Are Family" (#2 US, #1 R&B), the latter song becoming their biggest hit.

The album was written and produced by Nile Rodgers and Bernard Edwards of the group Chic.Sister Sledge's next album was 1980's Love Somebody Today. The album included the songs "Got to Love Somebody" (#64 US, #6 R&B, #34 UK) and "Pretty Baby".

Collaborating with producer Narada Michael Walden in 1981, they released the album "All-American Girls", yielding the title track single, which reached No. 3 R&B and No. 79 Pop in the U.S. and No. 41 Pop in the UK; and the single "Next Time You'll Know", which reached No.

28 R&B in the U.S. The sisters continued singing new material throughout the 1980s and 1990s, although not matching the success of the late 1970s. They achieved a hit with "Frankie" in 1985 (#1 in the UK).

In 1989 Kathy Sledge left the group to pursue her solo career. Joni Sledge produced and recorded the album "African Eyes" with her sisters Debbie and Kim Sledge in 1998 which was nominated for a Grammy as best produced CD, as well as the Live in Concert album in 1997.

In 2003, Debbie and Joni Sledge performed with three other female singers which included Debbie's daughters Amber and Camille in the PBS special, My Music: 70's Soul Superstars, which is also available on DVD.

Their most popular songs have been re-released and re-recorded several times in Europe, often in newly-remixed versions. Their song "Il Macquillage Lady" written by Joni Sledge is believe to be sampled for French electronic duo Daft Punk's 2001 track Aerodynamic although Daft Punk have denied sampling the song.

The sisters continue to perform collectively and individually worldwide. The four original group members were reunited in 2011 on Oprah Winfrey's "Women Who Rock" episode, highlighting their song "We Are Family" as one of the most requested songs of all time.