See the adorable photo Kate Middleton sent to fans for Prince George's 5th birthday

Look at that smile!

Prince George is one of the cutest royals around, so we're sure fans of the Cambridge family will have loved receiving their own mini portrait of him in the post. His parents Prince William and Kate have sent out thank you cards to fans who wrote in to wish George a happy fifth birthday in July.

Royal watcher Bradley Donovan-Baird, who goes by the handle @loopycrown3, shared a photo of the card on Instagram, revealing the sweet message on the back that read: "The Duke and Duchess of Cambridge thank you for writing as you did to Prince George on the occasion of his fifth birthday. This was most thoughtful of you and greatly appreciated."

Prince George and Charlotte's cutest moments together:

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The photo William and Kate chose to send was the official portrait of their son, which they released on the eve of his fifth birthday in July. George looked utterly adorable as he posed against a wall in his grandfather Prince Charles' gardens at Clarence House. He wore a white short-sleeved shirt with blue buttons and his trademark blue shorts, and flashed a big smile at the camera. The birthday portrait had been taken by photographer Matt Porteous just after Prince Louis' christening earlier in the month.

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George is believed to have celebrated his birthday on private island Mustique during his family's summer holiday. William and Kate were able to enjoy some downtime with their growing brood – George, three-year-old Princess Charlotte and newborn baby Prince Louis – as well as Kate's parents, Carole and Michael Middleton.

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While the Cambridges have done everything they can to make sure that George, Charlotte and Louis have as normal a childhood as possible, royal fans have been delighted this year as the elder siblings have been making far more public appearances.

George and Charlotte played starring roles at uncle Prince Harry's wedding to Meghan Markle in May. They also attended Trooping the Colour in June, waving to wellwishers from the iconic Buckingham Palace balcony. George and Charlotte also cheered on their dad William at a charity polo match in June. Their next big appearance will likely be at Princess Eugenie and Jack Brooksbank's royal wedding in October.

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