Serena Williams shares adorable video telling Olympia she's pregnant

The five-year-old had recently told her mum she was 'getting fat', which made the announcement even more hilarious when she finally revealed the truth. 

Serena Williams and her husband, Alexis Ohanian, recently shared the exciting news of their expanding family and their daughter, Olympia, couldn't be more thrilled about becoming a big sister.

In a heartwarming clip, the tennis champ's five-year-old had the most priceless reaction to seeing her mum's baby bump for the first time.

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'She did call me fat and got really stressed out'

The intimate moment was shared on Williams' new YouTube channel and was titled 'Olympia's Surprise'.

Williams begins the video by sharing, "I just took this test today and I’m super happy. I’m just praying it keeps working." As she speaks, she shares footage of a positive pregnancy test.

The couple kept their news a secret from their daughter until the day before they announced it publicly, during their appearance on the Met Gala red carpet.

"The reason I haven't told her is because she can't keep a secret," she explains.

But her daughter did notice something was up and made a small remark about her mum's growing belly.

"She did call me fat and then she got really, like, stressed out. She was like, 'Mummy, you’re fat,'" Williams jokes. "I tried not to take it personally, 'cause I'm like, super into fitness."

"Are you kidding me," Olympia asked. Image: YouTube

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'It turns out I'm not getting fat, but I have a baby in my belly'

The video then flashes to Williams and her husband, Alexis Ohanian, sitting down on the couch with Olympia, about to break the news.

"Remember how you’ve been praying for a little sister or brother?" Williams asks. "Well, we went to the doctor, and it turns out I’m not getting fat, but I have a baby in my belly."

Olympia's face immediately lights up and she looks at her mum's belly and says, "Are you kidding me?"

Her mum and dad then assure her that they're not kidding. "You're going to be a big sister," they both say excitedly. 

She couldn't contain her excitement. Image: YouTube

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'You've got a lot of work to do, you're going to be a big sister'

The primary schooler then jumps up and hugs her mum. "Oh my god, I'm so excited," she says, before jumping off the couch and racing around the room. She's so ecstatic she trips and falls but then gets back up. 

Williams then pulls up her T-shirt to show her bump, which only excites her daughter more. Olympia then dives backwards onto the couch chaotically as her parents look on in amusement. 

"You've got a lot of work to do. You've got a lot of work getting ready to be a big sister," Ohanian says, trying to instil a sense of seriousness in his daughter.  

"You've still got to help us keep it a secret for one more day, okay?" he says and she agrees.

And it appears she kept her promise and the announcement was kept under wraps as planned until the Met Gala. 

Thrilled! Image: Youtube

Originally published as Serena Williams shares adorable video telling Olympia she's pregnant