Serena Williams is teaching them young.
The 36-year-old tennis pro stars in a new tearjerker commercial for Gatorade that appeared to also star her 2-month-old daughter, Alexis Ohanian Jr. While this would have been the newborn's acting debut, a spokesperson for the beverage told AdAge that Williams is actually cradling a baby body double!
"While Serena intended to have Olympia make her screen debut as part of this film, her daughter was under the weather and unable to be on set, but the sentiment remains the same," a Gatorade spokeswoman said in an email.
In the ad, Williams is seen holding the infant while offering her some valuable life advice. As if that seem heartfelt enough, a slowed-down version of Alicia Keys' powerful song, "Girl on Fire," is also playing. "There are so many reasons to quit, but even more to keep playing," she tweeted on Monday along with the commercial. "Even if you don’t go pro, sports can teach you so much. So keep playing. #sistersinsweat."
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In the commercial, Williams begins, "Baby girl, I won't mind if you play tennis badly. I won't mind, if you choose, to never pick up a racket. But I beg you, in this game of life, please keep playing no matter what."
The new mom goes on to share her wisdom over scenes of young girls playing sports. "Just like it taught me, sports will teach you to be strong. You’ll discover the power and grace of your body. You’ll learn to move and you’ll learn the way to move others," she continues. "Sports will teach you the strength of your allies. Whether your bond is by blood or by ball, whether she shares the color of your skin, or the color of your jersey, you’ll find your sisters in sweat."
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"Sometimes you’ll score goals, sometimes you won’t. But the goals you’ll set, you’ll reach together," Williams adds. "You’ll find the courage to stand tall, work harder and speak louder on whatever playing field you choose in life."
She sweetly concludes, "So keep playing, my girl. Keep playing."
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It's been a busy few months for Williams! In addition to welcoming her first child, she also married her baby's daddy, Reddit co-founder Alexis Ohanian, last week in New Orleans, Louisiana.
Here's ET's inside look into the star-studded nuptials!