Kathy Byrne, the only child of Chicago’s first female Mayor Jane Byrne and successful trial attorney, died Thursday of lung cancer. She was 66.

Ms. Byrne was born in December 1957, the only child of William and Jane Byrne. Her father, a Marine pilot, died two years later when his plane crashed in a dense fog on his way to the Naval Air Station in Glenview. Jane Byrne died in 2014 at age 81.

Ms. Byrne was a plaintiffs’ attorney at the law firm Cooney & Conway for her entire career, along the way winning numerous multi-million-dollar jury verdicts and settlements involving people harmed by asbestos. The fire-resistant mineral, which has many industrial and commercial applications, is also a known carcinogen that can cause lung disease and other health problems.

“She was very committed to her clients who were victims of serious injury, and in particular to the disease mesothelioma, which is an asbestos-related disease,” her law partner Kevin Conway told the Sun-Times. “She was kind and very funny, and she was extremely well-liked by her partners and colleagues at the firm.”

Last year, she was named president of the Illinois Trial Lawyers Association, becoming the second woman to hold that title.

Other highlights include being named “Best Lawyer in America” by U.S. News and World Report and receiving a “Top Lawyers in Leadership” award in 2016 from the Women’s Bar Association of Illinois.

Conway said Ms. Byrne led by example and was a great motivator of young women.

“She encouraged a lot of young women attorneys that they could become leaders in the bar. There are a lot of young women attorneys who had been lawyers in recent years but she was very big on saying, ‘Yes, but you can also be significant movers and shakers and leaders in the bar,’” Conway said. “Sure enough, she had a number of people following her.”

Jane Byrne, who served as Chicago’s 50th mayor from 1979 to 1983, had a profound influence on Ms. Byrne as the two cultivated a close relationship.

“Her greatest legacy to me was that there is no ceiling,” Ms. Byrne said in a post on the law firm’s website. “You talk about a glass ceiling, but I’m unaware. I’m sure there probably is one, but I’ve never felt there was anything that I could possibly be prohibited from doing.”

Kathy Byrne grew up in the Sauganash neighborhood on the Northwest Side after moving to her grandparents’ home with her mother.

She initially aspired to be a political journalist. She was editor of her high school newspaper and called Washington Post reporters Bob Woodward and Carl Bernstein, who reported on the Watergate scandal that forced President Richard Nixon to resign, her heroes of the 1970s.

“Because of my mom, I was also pretty used to seeing TV cameras, and I thought they were in the catbird’s seat,” Ms. Byrne said in the law firm’s post.

After attending Saint Mary’s College of Notre Dame, she graduated from Loyola University School of Law in 1988, beginning at Cooney & Conway soon after.

Early in her career, a partner at the law firm gave her the book “Outrageous Misconduct: The Asbestos Industry on Trial,” which she “stayed up until 3 in the morning” to “read all in one night,” she said in the post.

The book changed the trajectory of her career, as she learned how companies knew the lethal dangers of asbestos but failed to dispose of the fibrous material in order to save money.

“It’s industrial murder, and [the companies] knew,” Ms. Byrne said. “By the time I finished the book I was thinking, ‘After law school, I’d kind of like to stay around.’”

Conway said one of Ms. Byrne’s greatest motivator was her privilege to represent people in Chicago because “she really loved the city of Chicago.”

In 2022, Kathy Byrne spoke at the ribbon-cutting ceremony for the Jane Byrne Interchange, the collection of ramps and roads just west of Downtown which connect the Dan Ryan, Kennedy and Eisenhower expressways. She wore one of her mother’s necklaces, which displayed the seal of the city and the words “One Chicago.”

“What the Jane Byrne Interchange does is, it brings Chicago together,” she said.

Ms. Byrne is survived by her son, Willy, a third-year law student.