Riley Gaines calls on famous female athletes to choose a side in trans debate. Here's who she's starting with

Riley Gaines, a former NCAA swimmer who speaks out against trans athletes competing in girls and women’s sports is calling on famous female athletes to join her cause.

"Each day for the next week I'm going to call on well-known female athletes to take a stance on this issue because silence is complicity...we need their voices," Gaines, who swam with the University of Kentucky, tweeted.

Her first tweet asked the world-famous tennis star sisters Serena and Venus Williams how they "feel about males competing against women."

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