Starr died in her sleep Friday at Saint John's Health Center in Santa Monica, where she had been convalescing after surgery, said her son Philip Starr.
In 1976, Starr founded the Los Angeles chapter of Parents and Friends of Lesbians and Gays, a gay rights and acceptance organization known then as Parent FLAG, now as PFLAG.
In 1979, she spoke on the steps of the U.S. Capitol at a march for gay rights — a seminal event often credited with uniting a then-nascent movement.
Two years later, she became PFLAG's first national president; she served in that capacity until 1986 and remained a forceful advocate for civil rights and, in later years, for the legalization of same-sex marriage.
Starr served at the helm of PFLAG during the onset of the AIDS crisis, said her longtime friend and collaborator Terry DeCrescenzo, founder of another advocacy group formed to reach out to gay and lesbian youth.
"In that time, a lot of us lost hope," said DeCrescenzo, 66, of Studio City. "Not Adele. And PFLAG became enormously important because it was rock solid.... She was a good woman. She'll be missed."
She was born in Brooklyn, N.Y., on Feb. 10, 1920, as Ida Seltzer, the daughter of an accountant and a homemaker. She never fancied her first name and changed it to Adele as a teenager.
In 1941 she married Lawrence Starr, an accountant. She remained mostly in the New York area through the end of World War II, in which her husband served as an Army translator and her brother, an Air Force bombardier, was killed in action.
In 1951, the Starrs visited a relative in the Los Angeles area and took to the region immediately, drawn largely by the weather. They soon settled in Brentwood, where Adele Starr helped her husband establish a private accounting practice.
She was primarily a stay-at-home mother. The Starrs had four sons and a daughter.
In 1974, Philip Starr, the couple's second son, sat his parents down and told them he was gay. Although the gay rights movement was well underway by then, he recalled, "being gay was still seen as a mental illness."
"And parenting was often blamed as the cause," Philip Starr said. "So parents really felt bad — they felt like they were bad parents."
His mother was upset, so Philip Starr directed her to a support group of sorts that eventually evolved into PFLAG.
Two years later, Adele Starr launched the Los Angeles chapter of PFLAG, modeled loosely after an existing group in New York. The group met first at her home but expanded quickly and soon began meeting at a Methodist church in Westwood, where families still meet today. Over the years, hundreds of families came and went.
"Initially the impulse was that the group was really important to her because she wanted parents not to suffer like she had — not to be isolated, to have a place to go," said Philip Starr, who has been with his now-husband, Michael Simengal, since 1974. The couple has a 19-year-old son.
In the early days, the meetings were "almost like an AA format," Philip Starr said. Some members even declined to reveal their true names. "As she got more involved, she realized how oppressive the environment was. She really became an activist," Philip Starr said.
In 1995, for instance, Adele Starr publicly lambasted a slate of conservatives trying to wrest control of an Antelope Valley school board; the group harbored a deep suspicion of multiculturalism and had declared gay relationships invalid.
Three years later, in a letter to The Times, the Starrs wrote that Philip was a devoted father and a successful businessman and taxpayer and deserved the "same rights and freedoms as others," including the right to "legally marry the one he loves."
"We cannot understand those arrogant people who have decided that a heterosexual lifestyle must be imposed on everyone and that they have a monopoly on morality," she wrote. "The American way is respect for diversity with the right to life, liberty and the pursuit of happiness."
Over time, Adele Starr's activism eclipsed that of her son; he recalled with a chuckle that she often had to remind him to pay his PFLAG dues.
She appeared at numerous conferences where, among other things, she preached her unyielding belief that sexual orientation was determined at birth.
DeCrescenzo said she'd developed a more nuanced view — that orientation was often the result of a combination of genetics and social learning. When DeCrescenzo proffered that view at conferences, she recalled that Starr often sneaked into the room to scold her in front of audiences: "That's just not true!"
"That she brooked no disagreement is simply, to me, a measure of the powerful commitment that mother love brings," DeCrescenzo said.
PFLAG is now a Washington-based nonprofit group with 200,000 members and supporters and 500 affiliates around the world. The group has since added transgender people to its mission, and its acronym now stands for Parents, Families and Friends of Lesbians and Gays.
She is survived by her husband, Larry; sons William, Philip, Robert and Andrew; daughter Margo Scoble; six grandchildren; and two great-grandchildren.
Services will be held at noon Monday at Mount Sinai Hollywood Hills, 5950 Forest Lawn Drive, Los Angeles.