The monstrously dominant Serena Williams, who reclaimed her spot as the world's No. 1 tennis player today (April 24), didn't ostensibly need additional strength. Still, the mom-to-be has nevertheless found some in her baby-to-be, whom she addressed in an open letter on Instagram this morning.

Williams, who vaguely confirmed she was five months pregnant in a Snapchat photo she uploaded earlier this month, has made a much clearer statement that she's expecting, and told her little boy or girl that she can't wait to meet.

"My Dearest Baby, You gave me the strength I didn’t know I had," she began her letter. "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. But most importantly, I am so happy to share being number one in the world with you.... once again today...from the world's oldest number one to the world's youngest number one. -Your Mommy"

And followers eagerly congratulated Williams on her tandem achievements, noting her baby will be in very capable hands.

"Once number one, always number one. Imagine how proud your baby will be once realizing what you represent for the rest of the world," one wrote, while another noted "God has truly blessed you. I believe you are the Greatest Athlete Ever regardless of gender."

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