Serena Williams pens heartfelt message for her baby after reclaiming No. 1 ranking

Serena Williams shared a heartfelt message for her baby after retaking the No. 1 ranking.

Serena Williams reclaimed the world No. 1 tennis ranking on Monday morning and then shared a short message for her baby on Instagram.

“My Dearest Baby, you gave me the strength I didn’t know I had. You taught me the true meaning of serenity and peace," Williams wrote. "I can’t wait to meet you. I can’t wait for you to join the players box next year. 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."

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Williams announced her pregnancy last week. Since Williams and her fiancé Alexis Ohanian are expecting the baby in the fall, she will miss the remainder of the year but plans to return to the tennis courts in 2018.

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Williams retook the No. 1 ranking after winning her 23rd Grand Slam title in January's Australian Open.