VIDEO: Pregnant Serena Williams Pokes Fun at Sister Venus' Reaction to Baby's Sex Reveal

 The second-time mom-to-be shared sister and fellow tennis legend Venus' hilarious reaction to the sex-reveal prank at her baby shower on TikTok

Serena Williams isn’t going to let Venus Williams live this one down!

On Tuesday, the pregnant tennis star, 41, poked fun at her big sister's hilarious reaction to the sex-reveal prank at her baby shower, in a video posted on TikTok.

“The greatest part of the reveal was watching #venuswilliams in the background,” Serena, who is expecting a baby girl, wrote in her caption.

In the clip, Venus, 43, hopped excitedly from side to side in the background as she watched Serena cut into a cake while expecting to see blue or pink sponge inside, indicating a baby boy or girl.

“Is Olympia going to be a big sister to a boy or a girl?" Serena’s husband Alexis Ohanian could be heard saying as Venus jumped up and down, clapping. “Once and for all, the color is ... "

GETTY; SERENA WILLIAMS/TIKTOK

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Venus leaned forward to get a closer look and opened her mouth in confusion as Serena revealed the cut slice to have yellow sponge. The camera then slowed down and zoomed in on Venus’ puzzled expression as X-Files-style music played and scientific equations displayed across her face. 

The funny clip was reposted from a video of Serena's baby shower and sex reveal shared on her YouTube channel Monday.

In the original video, Ohanian, 40, shared that he had organized a prank for Serena, their 5½-year-old daughter Olympia and guests as they were led to believe that the sex reveal of their baby would be revealed while Serena cut into a cake.

“I'm doing this because I want to troll her and Olympia into thinking that this is the reveal of Jelly Bean," Ohanian said in the clip, referring to the pet name they have for their baby on the way.

Added the Reddit co-founder, "She will cut into this cake and probably be disappointed and hopefully appreciate my troll. But we'll see. I don't know if she's gonna be a professional about it. She might see this cake come out, roll her eyes and say, ‘This guy had one job and he gave me a g--damn cake gender reveal.’ But we'll see. There's a reveal after the reveal.”

When Serena discovered that the cake was yellow inside, she smiled, put it on a plate and pretended to smoosh the slice into Ohanian's face.

“We are actually going to reveal Jelly Bean’s sex. The way we’re going to do it, though, is with a little style and some spectacular lights.” Ohanian said. He then requested the DJ to play some music and “draw attention to the heavens.”

The guests looked up and watched drones light up the sky, spelling out “Girl!”, with Serena, Ohanian and Olympia shouting their joy and guests applauding in reaction.