Serena Williams Dedicates a Heartfelt Post to Her Baby aka "The World's Youngest Number One"

Serena Williams is ready to give birth to a future champ of her own.

The tennis star penned a moving message to her unborn child (sorry, no gender reveal) on Instagram today, which also happens to be her fiancé Alexis Ohanian's birthday.

“My Dearest Baby, You gave me the strength I didn’t know I had. You taught me the true meaning of serenity and peace. I can’t wait to meet you. I can’t wait for you to join the players box next year,” the 35-year-old athlete wrote under a photo of herself lounging in a swimsuit. “But most importantly, I am so happy to share being number one in the world with you …. once again today. On @alexisohanian bday. ? from the world’s oldest number one to the world’s youngest number one. — Your Mommy.”

Serena first shared her pregnancy news last week with an internet-breaking Snapchat post. Once news of baby Serena made waves, it didn't take long for her fans, and the Math gods, to figure out that her being 20 weeks along means she had to be at least eight weeks pregnant when she won the Australian Open back in January. That's one bionic baby!

By the looks of her Instagram page, the mommy-to-be is currently getting some well deserved R&R on a beach getaway. The good folks at People confirmed with her reps that baby Williams is expected to arrive in the Fall.

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