This sibling R&B group Sister Sledge put the soul in disco with international party anthems like 1979’s “We Are Family.” • Debbie, Kathy, Joni, and Kim Sledge were born in Philadelphia into a showbiz family. Their father, Edwin Star, was a Broadway tap dancer, while their mother, Florez Williams, was an actress. Growing up, the sisters received vocal training from their grandmother Viola Williams, a former opera singer and protégé of civil rights leader Mary McLeod Bethune. • After graduating from Temple University, the sisters formed a group and released their debut album, Circle of Love, in 1975. • Their third album, 1979’s We Are Family, peaked at No. 3 on the Billboard 200 chart and yielded two Top 10 pop singles: “He’s the Greatest Dancer” and “We Are Family.” Written and produced by Nile Rodgers and Bernard Edwards of the group Chic, both tracks also topped the Billboard R&B charts. • Sister Sledge notched their third and final Top 40 US pop hit with a 1982 cover of Mary Wells’ 1964 Motown classic “My Guy.” • Produced by Nile Rodgers, Sister Sledge’s 1985 single “Frankie” reached No. 1 in the UK. • In 1989, Kathy left to pursue a solo career, though she continued to perform with the group for select shows. The four reunited for 2003’s Style, which would be their final album. • After Joni died in 2017, Debbie and Kim announced that they would continue to perform as Sister Sledge.