The mission encourages embracing colleagues with diverse personalities and lifestyles. (AP)

Martina Navratilova recently said that Venus Williams could play pro tennis until age 40, and that would make her compatriot, rival and friend Billie Jean King quite happy. 

That's because Venus and Serena Williams recently joined the Billie Jean King Leadership Initiative, in an announcement timed to 2018's Equal Pay Day, and the visibility for King's titular initiative would be grand for this, one of her many noble causes.

"Venus, in particular, helped us get equal prize money in the majors," King said in a telephone interview, per CBS News. "She was amazing. She really got Wimbledon to make the big step. Venus has always had the courage to step up. And Serena's the same way. They step up. I mean, Serena is not afraid to say whatever is on her mind." 

The BJK Leadership Initiative, founded in 2014 by King and her partner, Ilana Kloss, carries a mission to encourage workplace leaders to embrace colleagues with diverse personalities and lifestyles. Additional advisory board members include Kloss, Andy Roddick, Elton John, Jason Collins and Christiane Amanpour. Suffice it to say, the sisters Williams are in mighty good company. 

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