Alexis Ohanian Says Daughter Olympia Made Him a 'Better Man' in Sweet Tribute as She Turns 5

Alexis Ohanian Sr. Instagram

Alexis Ohanian is reflecting on his little girl growing up.

The Reddit co-founder shared a selfie with daughter Olympia, along with some other recent shots on Instagram Friday, as he reflected on everything she's changed since she was born five years ago.

"🍰🍰🍰🍰🍰 How are you already 5️⃣ @olympiaohanian ?? I love you more every single day, you've made me a better man, and I'm so grateful your mama brought you into this world 💪 I'm gonna Uppy you forever!" the proud dad wrote.

"I started @776fund thanks to you and it shares your birthday 😆 thanks @katelin_cruse @elisabethgarvin - these last two years have been otherworldly," he continued. "And thank you @christinatosi & @milkbarstore for a very memorable 'caking' session."

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Alexis and Olympia have been on hand to witness 23-time Grand Slam champion and mom Serena Williams compete in the US Open. Speaking on "A Conversation with Champions" panel ahead of the competition, the 40-year-old tennis legend said that she and Olympia share all the same interests – except the court.

"She's my little buddy," Williams said at the forum hosted by Sheinelle Jones and Dylan Dreyer of the Today show. "We do everything together. We go on dates and it's so cool because she likes everything I do except for tennis."

"She's really fun. I see a lot of my personality in her and it's just a great time to have her around now to see what I do on a daily."

RELATED: Serena Williams Says Daughter Olympia, 4 ½, Likes Everything She Does 'Except for Tennis'

Appearing on the cover of TIME's latest issue, Williams discussed how the shifting priorities in her life have led to her decision to retire from the sport after over 27 years.

"It's hard to completely commit when your flesh and blood is saying, 'Aw,' " she shared.

Noting that her desire to grow her family is leading to "this evolution" and how that is not the case for male athletes, she said that there is "no anger."

"I'm ready for the transition," Williams noted, adding that when it comes to being a mom, "I think I'm good at it, but I want to explore if I can be great at it."