Sarah Dash, a co-founding member of Labelle and “Lady Marmalade” singer, has passed away. She was 76 years old.

Patti LaBelle confirmed the sad news in an Instagram post on Monday (Sept. 20) and mourned the loss of her friend and former groupmate.

“We were just on stage together on Saturday and it was such a powerful and special moment! Sarah Dash was an awesomely talented, beautiful and loving soul who blessed my life and the lives of so many others in more ways than I can say,” Patti captioned the post. “I could always count on her to have my back! That’s who Sarah was… a loyal friend and a voice for those who didn’t have one. She was a true giver… always serving, always sharing her talent and her time.”

The Grammy Award-winning songstress further said that she is “heartbroken” by Sarah’s passing.

“I know that Sarah’s spirit and all that she has given to the world [will] live on! And I pray that her precious memory brings us peace and comfort,” she wrote. “Rest in power my dear sister. I love you always.”

Sarah, who was raised in Trenton, New Jersey; got her start as a founding member of the vocal group The Capris. After moving to Philadelphia in the 1960s and meeting Nona Hendryx, Patti Labelle and Cindy Birdsong, Sarah and the three singers formed their own group called Patti LaBelle and the Bluebelles. The group, which changed its name to Labelle after Cindy left in 1967, went on to release several acclaimed albums and hits, such as their 1974 classic, Nightbirds.

After the group disbanded in 1976, Sarah enjoyed a successful solo career. She released four solo albums, including her 1978 self-titled LP, and was inducted into the Grammy Hall of Fame in 2003.

See Patti Labelle’s tribute to Sarah on Instagram below.