Princess Eugenie’s Birthday Message For Jack Brooksbank On Instagram Shows A Rare Side Of The Couple — PHOTO

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Who said all the royals are reserved? Princess Eugenie's birthday post for Jack Brooksbank was equal parts silly and sweet. In celebration of Jack's 33rd birthday — his first as her husband, following their October 2018 royal wedding — Eugenie posted an adorable selfie of the pair grinning from ear to ear. (Fun fact: As People pointed out, it was actually the first selfie Eugenie ever posted on Instagram, too.) Quite possibly the only thing more delightful than the picture was the loving message the princess shared in the caption. She wrote:

"Happy Birthday to you, my one and only Jack. You are one of a kind and totally extraordinary. Nine birthdays and counting...to quote you from a few months ago "you light up my life" 🎂🎈🎉🎊 #birthday"

The "nine birthdays and counting" line, of course, refers to when mutual friends first introduced the couple during a Swiss ski trip nearly a decade ago. "We met when I was 20 and Jack was 24 and fell in love," she said said in an interview with BBC 1. "We have the same passions and drive for life." Jack sweetly added that it was "love at first sight."

As for the "you light up my life" part, chances are that came from a speech Jack gave at their wedding reception.

"Seventy five percent of his speech was to profess his love for Eugenie," Dr. Anthony Wallersteiner, Jack's former headmaster, told the Telegraph back in October. "He said his life lights up when she comes into the room. 'She lights me up,' he said. She makes him whole. His love for her was obvious."

Eugenie's social media shoutout may officially be a new tradition for the royal, who joined Instagram last March. For Jack's 32nd birthday, Eugenie posted another Instagram shot in which her now-husband was cracking up with laughter. “Clearly I said something funny this time! Sums up Jack in a nutshell!” Eugenie captioned the photo.

Even Eugenie's father, Prince Andrew, shared a birthday message for his son-in-law "🎉 Wishing Jack Brooksbank a very Happy Birthday!⁣⁣" read a post from the Duke of York's official Instagram account, along with a professional photo of Eugenie and Jack from their wedding.

Most recently, the newlywed's also joined Prince Andrew during an official royal engagement in March at the Royal National Orthopaedic Hospital, where she previously underwent spinal surgery.

"It is such an honor to be here today, I feel like my bones and my blood are a part of this building," she said during her speech at the event, according to Hello!. "I learnt on this visit today that we all share in something with this building because we care, and so to us it is very important that we are here opening this new building and that Jack, as my newly married husband on his first event has been able to come and see where I had my operation."

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That is but one of many causes and charity work close to Eugenie's heart. Even her wedding included an environmentally conscious twist. “My whole house is anti-plastic now," the royal, who's revealed in an interview for British Vogue's September issue. "And Jack and I want our wedding to be like that as well.”

Judging from Eugenie's birthday post, the couple is still very much in the honeymoon phase and seems as happy as ever.