Cissy Houston, who sang in a church choir as a child before emerging as an in-demand backup vocalist on pop and soul records and then as a gospel star, and who helped shepherd her daughter Whitney Houston to superstardom, died on Monday in New Jersey. She was 91.

Her daughter in-law Pat Houston confirmed the death, in hospice care, The Associated Press reported. Ms. Houston was being treated for Alzheimer’s disease.

Ms. Houston was a gifted stylist whose powerful voice and deep faith made her an influential figure in gospel circles for decades. She won Grammy Awards in the traditional soul gospel category for the albums “Face to Face” in 1997 and “He Leadeth Me” in 1999.

Before then, she had been among the busiest backup singers in the record business, providing vocal support for Aretha Franklin, Elvis Presley and many others. And for more than a half-century she was the choir director for the New Hope Baptist Church in Newark, where she got her start as a singer in the 1930s.

Ms. Houston was the matriarch of a singing dynasty that included her daughter, her nieces Dionne and Dee Dee Warwick and a cousin, the opera star Leontyne Price. She endured the deaths of her daughter, who drowned in a hotel bathtub in 2012, and of Whitney Houston’s daughter Bobbi Kristina Brown, who, in an eerily similar tragedy, was found unresponsive in a bathtub in her Georgia home in January 2015 and died six months later. Whitney Houston had struggled with addiction for many years despite her mother’s intervention.

Unlike her daughter, Cissy Houston achieved wider fame in her later years, but she was comfortable with that. As she told Jet magazine in 1998: “A lot of the things I’ve done have come late in life, and it’s like a whole new career starting up. I don’t have regrets about the way I planned and lived my life, and I am very proud of what I’ve become.”