"When [Mom sleeps], I go on adventures with daddy," read the caption on Serena Williams and Alexis Ohanian's daughter's own Instagram account


New moms don’t always have the easiest time staying well rested, but on Friday, 3-week-old Alexis Olympia shared a pic on Instagram of her mom Serena Williams getting some shut-eye.

“Mama never sleeps,” read the caption on the photo, posted to the newborn’s own Instagram account. “When she does, I go on adventures with daddy. ‘Come on!’ ”

In the photo, Olympia does look ready for an adventure, sticking out her tongue with her mouth wide open. Williams, 35, is snoozing beside her, cuddled up with a stuffed animal.

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The baby girl’s father is Williams’ fiancé: Reddit co-founder Alexis Ohanian, whom she was named after.

Ohanian, 34, and the tennis champion welcomed his namesake on Sept. 1. They introduced her to the world on Sept. 13, almost two weeks after her birth, 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!”

On Sept. 17, Ohanian shared a black-and-white photo of his and Williams’ newborn daughter writing, “Dad life is the greatest.”

“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,” he continued.

He posted another photo on Friday, captioning a photo of his snoozing daughter, “Out of office. This is Parental Leave life. She’s clearly dreaming up all the startups she’ll start… And Grand Slams she’ll win…. And….”

On Monday morning, Williams tweeted about how motherhood is still sinking in for her. “It’s very weird for me to believe I have a child … a KID. I’m a mom. A real MOM,” she wrote.

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

Ahead of Olympia’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,” Ohanian said during a talk-show appearance over the summer. “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.”

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.”