Don't expect Instagram pictures of a magical flower fairy-themed birthday party à la Blue Ivy, or a Unicorn of dreams celebration like North West's for Serena Williams' daughter Olympia next month.

The tennis champion has revealed that she and husband Alexis Ohanian won't be celebrating Olympia's 1st birthday in September because of their religion as Jehovah's Witnesses.

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Speaking at a press conference during the 2018 US Open this week, Williams told reporters (via E!): 'Olympia doesn't celebrate birthdays.

'We're Jehovah's Witnesses so we don't do that.'

The religion's official website JW.org explains that Jehovah's Witnesses do not celebrate birthdays, Easter or Christmas, because 'such celebrations displease God'.

Birthdays have pagan roots, and the Bible 'condemns the use of magic, divination, and spiritism', according to the religion.

The 36-year-old athlete recently spoke about what her religion meant to her, telling Vogue last year: 'Being a Jehovah's Witness is important to me, but I've never really practiced it and have been wanting to get into it.

'Alexis didn't grow up going to any church, but he's really receptive and even takes the lead. He puts my needs first.'

Meanwhile, Williams responded like a boss to French Open's imposed ban on her health-preserving sports suit by wearing a Virgil Abloh tutu and fishnets during her first round at the US Open.

Williams' catsuit was designed to help prevent blood clots which she nearly died from after the birth of her daughter. She explained that the catsuit makes her feel like a 'Warrior Princess.'

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French Tennis Federation President, Bernard Giudicelli, caused controversy when he told Tennis Magazine: 'We are going to ask the manufacturers to let us know what is coming. I believe we have sometimes gone too far.

'Serena's outfit this year, for example, would no longer be accepted. You have to respect the game and the place.'

Nike had the best response too with an image of Williams wearing the catsuit mid match, along with the tagline: 'You can take the superhero out of her costume, but you can never take away her superpowers.'

Too true.

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Naomi Gordon

Naomi Gordon is news writer mainly covering entertainment news with a focus on celebrity interviews and television.