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Princess Eugenie's Birthday Post For Princess Beatrice Reveals A Sweet Nickname

Sister-sister. When I think about the specifics of Princess Eugenie and Princess Beatrice's relationship, it feels like I'm reading a fictional book. They're two royal sisters born and raised in the U.K. but have somehow dodged the prying limelight and paparazzi that seem to plague and swarm their cousins, Prince Harry and Prince William. They're almost living the same lives, but not really... y'know? Take Princess Eugenie's birthday post for Princess Beatrice as an example. While Harry and William have likely stuck to formalities in the past, Princess Eugenie posted throwback photos of her sister similar to the way the Kardashian/Jenners wish their siblings a happy birthday. Sure, there was a lot less Calvin Klein underwear sponsorships in Eugenie's post, but you get what I'm going for here.

On Thursday, Aug. 8, Eugenie took to Instagram to wish her sister a happy 31st birthday. Fans were delighted, not only by the sweet childhood photos included in Eugenie's carousel, but also by the reveal of the cute nickname she calls her oldest sister.

Eugenie's birthday message read: "You have been bossing it since before I was born and continue to be the most wonderful person, friend and big sister... Happy Birthday to you Beabea!! Xx 😘 🎉🎊"

BeaBea???

Love that.

Also, love the phrase "bossing it."

Eugenie's pictures include an adorable toddler photo of Beatrice walking with a fiery-red-headed Sarah Ferguson, a sweet picture of the sisters as little girls, a few grownup selfies, and a cameo of the family dog.

While BeaBea is cute and all, I still stan for what her mom calls her... Trixie-Belle. This time last year, Fergie jumped on Instagram to help her eldest ring in the big three-oh with the note: "Happy birthday my Trixie - Belle so proud of you xx."

Who knew the name Beatrice lent itself so well to so many kickass nicknames?

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Meanwhile, the Royal Family kept it formal, calling Princess Beatrice by her full name and title in their Twitter message to her. Their note said: "Wishing Princess Beatrice of York a Happy Birthday! Her Royal Highness is the first child of @TheDukeOfYork and Sarah, Duchess of York and fifth grandchild of The Queen and The Duke of Edinburgh. #HappyBirthdayHRH"

I'm not a detective or anything, but I think the hashtag #HappyBirthdayHRH simply must stand for "Happy birthday Her Royal Highness," which is definitely — as Princess Eugenie might say — "bossing it." (I don't know, did I use that correctly Euge? Can I call you Euge?)

It's not clear how Princess Beatrice is celebrating her birthday, but it's fair to suspect she's toasting with her boyfriend Edoardo Mapelli Mozzi. She currently works and lives in New York City, which makes me feel like a person like me (a local-ish New Yorker) has a high chance of bumping into her during her birthday drinks. Sure, it's safe to assume she, a literal princess, and me, a literal freelance writer, might frequent different bars, but weirder things have happened.

Happy birthday, BeaBea! Tell me where I should have my Uber Pool driver drop me off so we can celebrate!