Tennis superstar Serena Williams has opened up about why she won’t be celebrating her daughter’s first birthday this weekend.

Alexis Olympia turns one this Saturday, but her mum says it won’t be marked with a large celebration by Williams and her husband, Alexis Ohanian. Speaking at a press conference at the US Open, the 36-year-old explained the parents had their reasons.

“Olympia doesn’t celebrate birthdays,” Williams said. “We’re Jehovah’s Witnesses, so we don’t do that.”

The American website for Jehovah’s Witnesses explains the reasoning:

“Birthday celebrations have pagan roots,” the site says, and the Bible condemns paganism.

“Although the Bible does not explicitly forbid celebrating birthdays, it does help us to reason on key features of these events and understand God’s view of them,” the organisation explains.

 

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Kids humble us. The other day on a flight home Olympia had so much energy and insisted on running up and down the aisle. When I finally got her to calm down and sit still, she threw up all over me and in the aisle. #ThisMama wants to remind all mothers the importance of supporting one another through the highs, lows, laughs and tears. _ Share your own stories of motherhood with hashtag #ThisMama. I’d love to hear them!

A post shared by Serena Williams (@serenawilliams) on Aug 26, 2018 at 1:12pm PDT

One glance at the parents’ social media accounts will show that Alexis is obviously celebrated daily by her parents in other ways. The proud parents have shared countless photos of the very cute baby, clearly demonstrating the joy she’s brought into their lives.

Williams has also used the time since she’s become a mum to speak openly about its challenges and her personal struggles with being a working parent.

The tennis champion has used her experiences to encourage other mums to do the same. Most recently, she shared a story of Alexis vomiting on a plane to start a discussion about the realities of being a mum.

It’s certainly been a year filled with highs and low for the athlete, who earlier this year had to withdraw from the Australian Open.

“I can compete – but I don’t want to just compete. I want to do far better than that and to do so, I will need a little more time,” she said.

“The memory of last year’s Open is one that I will carry with me, and (my daughter) Olympia and I look forward to coming back again.”

But the Australian Open will always hold a special place in Williams’ heart, and it has everything to do with her love for her child.

Fun fact my daughters initials are AO as in the Aussie open she won with me @AustralianOpen

— Serena Williams (@serenawilliams) September 28, 2017

A month after the birth, Williams confessed she was “having a hard time” posting about anything other than her daughter on social media, and tweeted that Alexis Olympia’s name was a tribute to Australia.

“Fun fact my daughter’s initials are AO as in the Aussie Open she won with me,” she tweeted.

The 36-year-old was in the very early stages of pregnancy when she won her 23rd grand slam at the Australian Open in January, 2017.