Adele Starr, the founder of the Los Angeles chapter of the support group Parents and Friends of Lesbians and Gays (PFLAG), has died at 90 in California, the Los Angeles Times reported.

Starr died in her sleep on Friday while recovering from surgery in a hospital.

After her son Philip Starr announced he's gay in 1974, Adele Starr began attending a support group that would later become PFLAG.

She overcame her initial hostility to her son's sexual orientation to become a leading ally in the gay rights movement. In 1976, she founded the Los Angeles chapter of PFLAG, and went on to become the group's first president in 1981.

“Adele Starr was one of the pioneers of PFLAG,” Jody M. Huckaby, executive director of PFLAG, said in a statement. “It is because of her commitment to organizing the many people who were working for the common goals of equality for all into the organization that we now know as PFLAG that we have gained the strength, prominence and ability to become the voice of parent and allies united for equality.”

Starr was a vocal supporter of gay marriage. “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 and her husband Larry wrote in a 1998 letter to The Times.

She is survived by her husband and their five children.