Why Serena Williams called Kate Middleton her 'number one'

In an interview with InStyle Magazine, Serena Williams has opened up about her friendship with the Duchess of Cambridge.

When responding to the question: "OK. Since this is our first-ever Badass Women issue, who do you think is badass?" she listed two women that are well-known badasses and one surprise.

"Well, obviously Beyoncé. That goes unsaid. Rihanna goes unsaid. Kate Middleton!"

The interviewer agreed, "Could you imagine having a baby and then, right after, you put on makeup and go out to greet the public?"

Serena replied, "No. And she was… standing! So she's officially No. 1."

In the same interview, Serena revealed what attending the royal wedding was like:

"It was super fun. You know, I've known Meghan [Markle] for years, so it was good to see my friend happy."

And when asked about her beautiful outfit that she paired with sneakers for the event she explained her reasoning:

"I was supposed to wear heels originally, and I'm thinking, "C'mon, Serena—reception. Heels or shoes? Heels or shoes?" I decided to go with the shoes [laughs]."