Eleanor Elkin, 103, of Philadelphia, whose experience as the parent of a disabled foster son led her to become a fierce advocate for the rights of the intellectually and developmentally challenged, died Wednesday, Dec. 4, of heart failure at her daughter’s home in East Earl, Lancaster County.

Mrs. Elkin became an internationally recognized speaker and advocate for the right to education and self-determination on the part of disabled people. She hoped to change public attitudes toward them from pity and exclusion to acceptance and inclusion.

Celia S. Feinstein, executive director of the Institute on Disabilities at Temple University, which studies impediments faced by the disabled, said Mrs. Elkin was a trailblazer for disability rights in Pennsylvania and nationally.

“She reminded us all that each and every person, regardless of their need for support, can live successfully in the community of his or her own choosing,” Feinstein said.

Mrs. Elkin was born in 1916 in Philadelphia to Charles and Augusta Scott. She graduated in 1934 from Germantown High School. Although busy with classes, she babysat Grace Kelly, later Princess Grace of Monaco, the family said.

Mrs. Elkin met Philip Elkin in her early 20s. They married in 1939.

The Elkins had no biological children. They had a foster son, Richard Elkin, and later, an adopted daughter, Margot Arden. The couple wanted to adopt Richard, too, but the state would not allow it because he was disabled, the family said.

When Richard was 2 years old, he was taken away from the couple and placed in a state-run residential facility. The boy became sullen and ill, the family said, and the Elkinses had to petition the courts to win his return home.

Realizing that parents of children with disabilities needed help with advocacy, Mrs. Elkin founded a mothers’ support group in Bucks County. That, in turn, paved the way for the ARC of Bucks County, a nonprofit that provides services for people with disabilities and support for their families.

She fought for Richard to attend a preschool at the University of Pennsylvania. By the time he entered first grade in Doylestown, where the family then lived, she had persuaded school leaders to create a classroom for him and others with special needs. Richard remained in public school through 1966, when he transitioned to a workshop for people with disabilities.

In addition to founding the ARC of Bucks County in the 1950s, Mrs. Elkin also helped develop the Pennsylvania ARC, becoming the organization’s president in the 1960s. She became a vice president of the national ARC, now the ARC of the U.S., and was its president in 1967 and 1968.

Mrs. Elkin continued her affiliation with ARC as a member of its international board of directors. In that role, she traveled the world, attending conferences and workshops. “Even on pleasure trips, Eleanor always managed to stop and see a school or a residential home for people with disabilities,” the family said.

Normally gentle, she could be fierce when wading into a fight, the family said. Some of the battles were intense. “She never tired of telling the story of being hung in effigy, along with her friend, while the two were investigating conditions at a state school and hospital in Western Pennsylvania,” the family said.

She stepped down from her ARC board position in the 1980s to care for her husband, who was ill. He died in 1991. The couple’s son, Richard, died in 2008.

Mrs. Elkin was the recipient of many awards but was proudest of lobbying for closure of the Pennhurst State School and Hospital in 1987, and for her work with staff at the Public Interest Law Center of Philadelphia on the state’s right to education law.

Mrs. Elkin’s story was told in a play, A Fierce Kind of Love, by Suli Holum in 2016. Her personal papers are in the Temple University archives.

She is survived by her daughter, Margot Arden, three grandchildren, nine great-grandchildren, and nieces and nephews.

Memorial services will be at 11 a.m. Saturday, Dec. 21, at Summit Presbyterian Church, 6757 Greene St., Philadelphia. Mrs. Elkin donated her body to science through the Humanity Gifts Registry.

Donations may be made to the ARC via https://thearc.org/get-involved/ways-give/.