It’s no secret that Serena Williams and Meghan Markle are great friends. However, the Duchess of Sussex proved this year just how committed of BFF she is.

Williams recently revealed how Markle traveled across the pond for the first time with her four-month-old son Archie Harris to watch her play in the U.S. Open.

Markle was in attendance for Williams’ match against Canadian star Bianca Andreescu in the Open’s final in September. Speaking to Access Hollywood, the tennis legend revealed some of the details of the trip.

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“She flew all the way with a newborn to see me play in New York and flew all the way back that night, and I probably couldn't have done that,” she said.

During the Open, it was known Markle attended, however, it was widely assumed that baby Archie did not make the trip. Williams says Markle is one of the most amazing people she knows for her dedication to support.

“I'm not sure that many people can relate on that level, I don't think I can,” she told the celebrity news outlet. “I just think she's the strongest person I know, the nicest, sweetest… It really does show you what an amazing person she is and that's just one of the many things she does for me.”

Serena Williams and Meghan Markle reportedly met at a Super Bowl party in 2010 and have since been inseparable. Serena was one of the high profile American guests at Meghan’s wedding to Prince Harry in May 2018.