Story highlights She was found dead in her Phoenix home, publicist says

Sister Sledge's big hit was "We Are Family"

(CNN) Joni Sledge, a founding member of the R&B vocal group Sister Sledge, was found dead Friday in her home in Phoenix, publicist Biff Warren told CNN on Saturday. She was 60 years old.

The Sledge family was shocked by her death as she had not been ill, Warren said. The cause of death was unknown.

The group of sisters were best known for the 1979 dance anthem "We Are Family." Other hits were "He's the Greatest Dancer" and "My Guy."

"Yesterday, numbness fell upon our family. 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 band said Saturday in a statement posted on their website and Facebook page.

We love you Joni. pic.twitter.com/6Zxj6gLoQh — Sister Sledge (@SisterSledge_) March 12, 2017

Joni Sledge was born in 1957 in Philadelphia, according to the Internet Movie Database . She came from a musical family and her parents were entrepreneur/actress Florez Sledge and Broadway performer Edwin Sledge, the official Sister Sledge website says.