Yet both sisters are passionate about helping others achieve equality both on and off the court. The Williams sisters were in New York City this week taking part in the Tie Break Tens tennis tournament. In honor of International Women's Day, the sisters spoke to CNBC about work-life balance, paid family leave and equality in the workplace.
Serena Williams has returned to tennis just months after giving birth to daughter Alexis this past summer. Playing in her first singles tennis match this week, the 23-time Grand Slam singles winner says having a child has changed her outlook on tennis.
"It's different now. You have different priorities," she says. The 36-year-old says she now plans her schedule around her daughter's and likes to be home at a consistent time at least four or five times a week. "I just work around it," she says.
"Serena's an amazing mom," says sister Venus. "She really puts the baby first and has found a balance and never changed. If I'm a mom one day, I hope to be just as good as her."
As the sisters gear up for their next tournament in Indian Wells, California, Serena says she's just happy to be back on the court. "I don't even really know what to expect from myself. I'm just happy that I can still do this and I would love to do it again."
Williams also says being a mother has changed the way she looks at paid time off. "I hear so many of my friends say 'We got four weeks off.' I couldn't have gone back to any job in four weeks. I definitely think it's important to get more time off."
Both Serena and Venus have long used their star power to advocate for equal pay for women and minorities. More than a decade ago, Venus famously fought Wimbledon on the disparity between men and women's prize money. Her fight paid off. In 2007, Wimbledon announced they were eliminating the wage gap and men and women would be paid equal prize money.
Serena, the highest-paid female athlete in the world, has been vocal about helping black women close the pay gap, citing that black women earn 17 percent less than their white female counterparts and 63 percent of every dollar men are paid.
"Together we will change the story — but we are going to have to fight for every penny," she wrote in an op-ed for Fortune.
The William sisters say that while progress has been made during their careers, they aren't done fighting. "I think there's a lot happening," says Venus. "But there's a lot more that needs to happen around the world with pay discrepancies. As much as I can be a part of it — I am."
"I feel like we're getting there," says Serena. "We need females supporting it and men advocating for it."
When it comes to fighting for equal rights, the sisters say that while it can be intimidating, it's important to remember they're fighting for long-term changes. "We might not get it today, but we want a future better for maybe my daughter, or her daughter, and so that's what we really are fighting for."
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