Serena Williams and Alexis Ohanian celebrate the birthday of one-year old daughter Olympia

Tennis star Serena Williams and her husband, Reddit co-founder Alexis Ohanian, had a big reason to celebrate this Labor Day – the first birthday of daughter Olympia.

Ohanian shared pictures of Olympia on Instagram to mark the occasion.

"1 year ago today, you changed our lives forever, @olympiaohanian my adventure princess

Ohanian has been know to share his emotions regarding his wife and daughter on Instagram, and has been Williams’ biggest cheerleader when she returned to the tennis court this this year. Williams’ made it as far as the Wimbledon final earlier this summer, and is currently competing in the U.S. Open.

He's has been an outspoken advocate about strong, successful women and the importance of being a supportive partner.

During an interview with Good Morning America earlier this year, Ohanian said, "There's probably a lot of guys who would feel threatened in a situation with a partner who is extremely talented and successful. It seems kind of absurd to me, though, because all of that success and all of that greatness is something that you should be championing."

He is just as outspoken when it comes to showing pride in his daughter. He and Williams have already created an Instagram account for Olympia. Despite the social media attention, Williams says that they won’t be celebrating Olympia’s birthday with a party.

During a press conference for the U.S. Open, Williams said that Olympia doesn’t celebrate birthdays because Jehovah’s Witnesses don’t do that.

Williams shared a post about Olympia a week ago, touting her daughter’s energy and enthusiasm during a plane ride, and encouraging others to share their own joys of motherhood.