Tennis legend and Watch Her True Story 9 Onlinemama-to-be Serena Williams just celebrated her pregnancy with a star-studded '50s-themed baby shower at Nick's 50s Diner in West Palm Beach in Florida.

Williams' super cute bash was attended by some of her celeb pals, like Kelly Rowland, Ciara, La La Anthony, Eva Longoria, and of course, her equally talented sister, Venus Williams.

Party goers pulled all the stops with spot-on colorful costumes and even the famously huge '50s hair bows. They even posed in front of a cherry red pickup truck that was parked outside the old school diner.

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The older Williams sister and soon-to-be auntie burst out big polka dots to celebrate the occasion.

Williams' famous friends took to social media to share all the cool photos from the "Baby O's Diner" party with the hashtag #ShakeRattleandRoll2017 and um, also to give us major FOMO.

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This comes months after the 23-time Gland Slam champion accidentally announced her pregnancy in April via a Snapchat of her baby bump bearing the caption: "20 weeks."

However, Williams and her fiancé and co-founder of Reddit, Alexis Ohanian, have revealed that they don't know the gender of the baby and have decided to keep it that way until the birth.

Williams confirmed this through a note she shared on Instagram a couple of months ago:

View this post on Instagram

Based on how the baby shower went, we can only imagine how amazing this baby's 1st birthday party theme will be.

Congrats, Serena and Alexis!

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