Princess Eugenie has paid the sweetest tribute to her older sister, Princess Beatrice, in honour of her 34th birthday on Monday.
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The royal, who shares an extremely close bond with her sibling, took to Instagram to share a lovely series of photos of them together, including a never-before-seen snapshot with their cousin Zara Tindall.
WATCH: Princesses Beatrice and Eugenie and mum Sarah tear up as they meet teenage cancer patients
"Happy birthday to my special big sissy. Love you so much," Eugenie wrote alongside the post.
Fans were quick to comment on the tribute message, with many wishing Beatrice many happy returns, while others remarked on the sweet picture with Zara.
Princess Eugenie shared a sweet tribute message to Princess Beatrice on her birthday
While the Princess is likely to spend the day in private with her husband Edoardo Mapellli Mozzi and their baby daughter Sienna, the celebrations will no doubt be extra special this year. It marks the first time Beatrice has toasted her birthday as a mother.
SEE: Royal sisters Beatrice and Eugenie have surprisingly different parenting techniques
Eugenie, 32, shares an incredibly close bond with her sister, Beatrice, with Eugenie proclaiming in an interview with The Telegraph in 2008 that: "Mummy, Bea and I call ourselves 'The Tripod', they are my best friends in the world."
Meanwhile, Beatrice's mother Sarah Ferguson opened up about both of her daughters after their appearance at the Queen's Platinum Jubilee - and how proud she is of everything they have achieved.
Speaking on The Graham Norton Radio Show with Waitrose in June, Sarah confessed she "screamed at her TV" when her daughters made their way to St Paul's Cathedral for the Thanksgiving Service on June 3.
"Everyone else looked a bit... very serious and they were smiling and really thanking their grandmother for these 70 years," she explained, adding: "I was watching the telly like, 'Well done girls, you're smiling.' I can't get over how beautiful my girls look. When they went off to the Jubilee Thanksgiving Service, wasn't that just beautiful?
The royal sisters are extremely close
"I couldn't get over it. There was Beatrice in blue and Eugenie in orange and they are smiling, right. So grateful... I was screaming at the TV."
Of their upbringing within the royal family, Sarah stated: "I think the way Beatrice and Eugenie are behaving and have behaved, it's just extraordinary."
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