Alexis Ohanian Celebrates Daughter Olympia's 'Final Days of Being Six' with Trip to N.Y.C.: 'My Heart Is Full'

Alexis Ohanian can't believe his little girl is already 7.

On Monday, Sept. 2, the dad of two, 41, shared a carousel of photos on Instagram from his trip to New York City with daughter Olympia, who recently turned 7. The father-daughter duo can be seen going to a play together, visiting Milk Bar and spending time at the American Girl Store.

In his caption, Ohanian took a moment to reflect on how big his older daughter is getting. "Beautiful weekend with our SEVEN year old Alexis Olympia Ohanian Jr. 🥹 My heart is full."

"We got to celebrate the final days of being six in Papa's birthplace. 🗽 @olympiaohanian your mama and I love you more with every passing year. My life changed September 1, 2017 🙏 thank you," Ohanian wrote.

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Ohanian shares daughter Olympia and Adira, 12 months, with wife Serena Williams.

Earlier in August, the retired tennis pro, 42, shared a couple of posts on her Instagram as she took a minute to share that it has been a year since she welcomed her daughter Adira. Williams first shared a series of photos from her maternity shoot, which showed the mom of two wearing a see-through, flowy pink dress and lying on a bed of flowers.

Williams also included photos of herself in a sports bra, showcasing her bare bump in black-and-white photos.

"A year ago today - August 15th - I gave birth to my second baby girl, Adira River Ohanian. She is a true light. Here’s a peek inside my maternity shoot. @adiraohanian," Williams wrote in her caption.

In May, Ohanian spoke with PEOPLE about his daughters' relationship, saying that Adira brings out the "maternal" spirit in Olympia.

"She's able to have a lot more fun with her sister in terms of playing. You can already see the interactions between them. It's a big age gap, and Olympia has a little bit of that maternal spirit. She's like, 'This is my baby,' and it's great to see them together," Ohanian shared.

"They play and sort wrestle and all that. We're very lucky because Adira's got a great personality and Olympia does too, plus she's so excited to be a big sis. So seeing the two of them interact with each other has been a special kind of fun. Adira's getting more mobile and ore vocal, and it's only going to get even more fun."

He joked, "I guess at some point they're going to fight over things, but for now, let me live in bliss."