Alexis Ohanian showed off a new photo of his and Serena Williams' daughter Alexis Olympia on Instagram Sunday, writing about "dad life"

By Lindsay Kimble
September 18, 2017 03:20 PM
Credit: Alexis Ohanian/Instagram

Alexis Ohanian‘s daughter already has him wrapped around her little finger.

“Dad life is the greatest,” Ohanian wrote on a Sunday Instagram post, sharing a new black-and-white photo of his and Serena Williams’ newborn baby girl Alexis Olympia.

Continued the Reddit co-founder, “Entrepreneurship is all-consuming, it’s sleepless, we call our startups our ‘babies,’ we are ridiculously proud of them, and we pour all of ourselves into them – but she is already all that and more, she is my legacy.”

On Monday morning, Williams Tweeted, “It’s very weird for me to believe I have a child… a KID. I’m a mom. A real MOM.”

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Ohanian and the tennis champion, 35, welcomed his namesake on Sept. 1, and introduced her to the world on Wednesday with a montage of photo and video moments from Williams’ pregnancy.

In one clip, Williams admitted that she had “a lot of complications” during her delivery, adding, “But look who we got — we got a baby girl!”

Credit: Karwai Tang/WireImage

PEOPLE confirmed Williams’ pregnancy in April after the athlete inadvertently revealed on Snapchat that she was expecting. Williams and Ohanian, 34, were engaged in December.

Ahead of their daughter’s birth, the couple shared that they had decided to leave the baby’s sex a surprise, though both said that they felt they were having a girl.

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“[Serena] won the Australian Open while pregnant. And she remarked that she feels like it has to be a girl because everything that that baby went through and handled like a champ, only a woman could be strong enough to take on,” Ohanian said during a talk-show appearance over the summer.

The pro athlete echoed her fiancé’s sentiment to Vogue in its September issue, revealing, “I have a strong suspicion that it’s a girl.”