Rest in peace, Joni Sledge.

The singer from the popular 1970s female vocal group Sister Sledge died on Friday, March 10, at just 60 years old. She was found dead in her home in Phoenix.

Her family was shocked by her sudden passing because she has not been previously ill, her publicist Biff Warren told CNN. The cause of death has yet to be determined.

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“Yesterday, numbness fell upon our family,” the Sledge family said in the statement posted to the band’s official Facebook page. “We are saddened to inform you that our dear sister, mother, aunt, niece, and cousin, Joni passed away yesterday. Please pray for us as we weep for this loss. We do know that she is now eternally with Our Lord.”

The remaining members of Sister Sledge — Joni’s sisters Debbie, Kim, and Kathy Sledge — asked fans to give the family privacy while they mourn their loss.

The Philadelphia-based disco and R&B group first rose to fame in the 1970s and their 1979 hit song “We Are Family” became a dance anthem — which reached the No. 2 spot on the Billboard Hot 100 charts and also earned the sisters a Grammy nomination. Their other hit, “He's the Greatest Dancer” was revived two decades later when rapper Will Smith sampled the beat for his 1997 song “Gettin’ Jiggy Wit It.”

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Celebrities took to social media to mourn Joni’s death, and TV personality Ru Paul shared cover art for Sister Sledge albums and a screenshot of their best hits under the hashtag “#SisterSledgeForever.” La Toya Jackson, the late Michael Jackson’s sister, also posted a heartfelt tribute to Joni after her death.

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“So sorry to hear that Joni Sledge has passed, my condolences to her family, friends and love ones,” the 60-year-old wrote on Twitter. “#SisterSledge we are family!”