BOCA RATON, Fla. — All the medical advancements that helped save Chris Evert’s life could not save her sister. Jeanne Evert Dubin died of ovarian cancer in February 2020, at age 62, her illness discovered only after it had reached its deadliest stages.The first indication for Chris that something was wrong came as she and her younger sister hustled through an airport terminal for a flight to Singapore for the women’s tennis championships. Chris saw that Jeanne, a former professional player herself, was breathing heavily, unable to keep up. Not long after that, Jeanne was diagnosed. Two years after that, she was gone.“Why her?” Evert said recently in an office at the tennis academy that bears her last name. “I’m the older one. I’m supposed to go first. Sometimes I think that.”Out of that sorrow came a critical warning for Evert, an alert she is determined to spread to the world so that other lives, like hers, can be saved, too.In the months after her sister’s death, doctors called Evert with news that a blood sample taken from her sister before she died had only recently revealed a harmful variant of the BRCA1 gene, increasing her likelihood of breast and ovarian cancers. Within days, Evert, 67, was tested and learned that she, too, possessed the same genetic condition.In December, she underwent a preventive hysterectomy, and lab tests discovered cancerous cells in the tissue. She would have to go back into surgery as soon as she healed so surgeons could see if more cancer was present, and if so, how far along.Nothing else was discovered. It was determined that Evert had been in Stage 1, but if she had not known about the need for genetic testing, doctors told her that within four months, she would have been in Stage 4, like Jeanne.For the six months after her surgery, Evert underwent chemotherapy, with the nausea and “cruddy” feeling, as she described it, forcing her away from her beloved tennis courts — but only for five days at a time. Then, she was back to work, traveling with the United States Tennis Association Foundation, and on the court, lending her expertise to kids for three more weeks until she went back for her next treatment, and the cycle resumed.Evert after winning the 1983 French Open.Dominique Faget/Agence France-Presse — Getty Images“She handled it with the same focus that made her an 18-time Grand Slam champion and an icon,” said her younger brother, John Evert, who runs the Evert Tennis Academy. “She accepted it and shared it with people to help others by telling her story. She is still a champion.”Evert will be back at the U.S. Open, which she won six times, to work the broadcast for ESPN. It will be her second tournament, after Wimbledon, since announcing in May that she is cancer free, with a 90 to 95 percent chance it will never return. She will also host the U.S.T.A. Foundation’s gala on Monday, the first night of tournament.It is one of the most critical fund-raising events for the organization, for which Evert has proved to be every bit the champion she was on court, even continuing to work through her treatments.Since volunteering to be chairperson of the U.S.T.A. Foundation — the charitable arm of the U.S.T.A. that runs tennis and learning centers for as many as 160,000 underserved children each year — Evert has blossomed into one of the most effective leaders the organization has ever seen. During her term, which began in 2019, she has overseen the expansion of the National Junior Tennis and Learning program, and helped the foundation take in $30 million in grants and donations, most of which is targeted to help children of modest means reach their potential.After all, who could easily say no to the personable Evert, whose 18 Grand Slam singles championships are tied with Martina Navratilova’s for third most in the Open era, and her 90-percent winning percentage is the highest in that era. Her athletic pedigree and competitive focus, combined with her genuine and engaging nature, make Evert a near-perfect candidate for the leadership role.Evert will be back at the U.S. Open, which she won six times, to work the broadcast for ESPN.Sonia Moskowitz/Getty Images“Since her involvement, she has elevated the foundation to new levels,” Dan Faber, the chief executive of the U.S.T.A. Foundation, said. “She’s really enhanced our mission into what I would call a grand slam charity.”In 2020, when many charitable organizations struggled to raise money in the midst of the coronavirus pandemic, Faber had an advantage in the sports legend. Once, he set up a video conference call with a wealthy donor, who Faber hoped would contribute $250,000. With Evert on the line, the man was so delighted, he brought his wife into the conversation and by the time it ended, their check was for $1 million.It was not because she regaled them with tales of playing Navratilova and Steffi Graf but because of her passion for the cause, and expectations are that 2022 could be the organization’s best year ever for fund-raising, Faber said. Evert downplays her contributions with the same natural modesty she displayed as a player who rose to stardom from public tennis courts.“What’s so hard about getting on a Zoom?” she said. “Look, I had the time. My kids were grown up. Sure, it makes me feel good to give back, but it makes me really feel good to engage with kids that don’t have the resources and don’t have opportunities. When I travel and see these programs at work, I see how important they are.”Evert knows this firsthand. When she and her four siblings were growing up, their father, Jimmy Evert — a tennis instructor at public courts in Fort Lauderdale, Fla., for 49 years — insisted his children play tennis after school. Long after Chris Evert had turned it into a successful career, she asked her father why he made them all play. “‘To keep you kids off the streets,’” she said he told her.“What, did he think that I was going to join a gang or something?” Evert said with a chuckle. “But as I got older I, he got smarter in my eyes. Idle time is not good for kids, especially in this day and age. You have to keep them busy in a positive way.”Jimmy Evert, and his wife, Colette, a eucharistic minister, imbued their children with a sense of charity alongside the tennis, Chris said. Jimmy gave free tennis clinics to locals, and Colette worked with the Salvation Army, encouraging the children to go through their clothes once a month for donations.Later, Chris Evert’s involvement with the U.S.T.A. Foundation sprang from her work, alongside John Evert, on a scholarship program they started with the U.S.T.A. to honor their father, who died in 2015. Chris was already traveling and making appearances for the Jimmy Evert Fund, why not expand her portfolio to include the entire foundation? It was a natural fit and an irresistible confluence of talent, commitment and charm.“I liked it more than I thought I would,” she said. “I like not only being with the kids and seeing the smiles and the hope in their eyes, but they are also learning. I really feel it.”As Evert continues her recovery from the cancer and the treatments — she says she still does not feel even 85 percent — she pushes forward in her work, helping guide the Evert Academy while also establishing new heights for the U.S.T.A. Foundation.Evert with students at her tennis academy in Boca Raton, Fla.Melanie Metz for The New York TimesThe job has an informal three-year term limit, but Evert, who was the first woman to win 1,000 singles matches, the first to be ranked No. 1 in computer rankings and the first to be named sole winner of Sports Illustrated’s athlete of the year in 1976, is accustomed to setting new standards.“I’m going to demand I stay on,” she said. “They can’t take it away from me. It’s getting bigger and bigger. We are going into more cities, which I like, and helping more kids. That’s what it is all about, right?”Once she is fully recovered, Evert said she intended to help raise more awareness and money for cancer research. She recalled a difficult conversation she had with her sister.Jeanne was always the one taking care of others, and she largely ignored early symptoms, thinking they were a regular part of aging. Why, Chris asked, if Jeanne felt something wrong in her body, didn’t she go to a doctor sooner? Upon seeing the look in her sister’s eyes, Evert immediately regretted posing the painful question, and Jeanne requested she never ask it again.Evert paused after telling the story. But now, Evert sees it as her duty to raise that same issue of early detection with the entire world.“Because of my sister’s disease and her death, I’m living,” Evert said. “I think about that all the time. It’s so important for people to know their family’s medical history. Be proactive.” More