The music world is mourning a tragic loss. 

Cissy Houston—the mother of the late Whitney Houston and a Grammy-award winning singer—has died, her family confirmed to the Associated Press Oct. 7. She was 91. 

Cissy passed away in her New Jersey home on Oct. 7 while under hospice care for Alzheimer's disease—a type of dementia that affects memory, thinking and behavior—the outlet reported.

“Our hearts are filled with pain and sadness,” her daughter-in-law Pat Houston shared in an Oct. 7 statement to the Associated Press. "We lost the matriarch of our family."

Noting that her mother-in-law's contributions to music were "unparalleled," Pat went on to describe Cissy as a "strong and towering figure in our lives."

Cissy rose to fame in the 1960s as one-third of the R&B girl group The Sweet Inspirations, which also comprised Doris Troy and her niece Dee Dee Warwick. The trio earned acclaim for their work as backup singers for artists such as Otis Redding, Dee Dee's sister Dionne Warwick, Van Morrison and Elvis Presley. 

Over the course of her decades-long career, Cissy also made an impact as a solo artist. As a session singer, the New Jersey native has recorded over 600 songs across multiple genres. Plus, she won two Grammy awards in the Best Traditional Soul Gospel Album category for her solo records Face to Face (1997) and He Leadeth Me (1998).

And Cissy—who authored the books He Leadeth Me, How Sweet The Sound: My Life with God and Gospel and Remembering Whitney: A Mother’s Story of Life, Loss and The Night The Music Stopped—has been candid about how her spirituality has kept her going over the years. In fact, she shared that her faith was how she coped with the 2012 death of her daughter Whitney. 

"I believe totally in God," she said during a 2013 book signing, per USA Today. "I know with every ounce in me he loved her and she loved him, and I love him."

Cissy is survived by her son Michael Houston, who she shares with ex-husband John Russell Houston, and son Gary Garland, who she shares with ex-husband Freddie Garland, as well as granddaughter Rayah Houston and niece Dionne. 

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