Taking to Twitter, the Queen's social media team shared a heartwarming video along with an endearing message which read: "Thank you @IrishGuardsBand for playing Happy Birthday to mark Prince George's birthday today!"
WATCH: The Band of the Irish Guards put on a special performance
The tweet ended with: "The Duke of Cambridge is the Colonel of the @irish_guards."
In the clip, a magnificent band of trumpeters could be seen standing in a semi-circle as they performed the merry birthday tune. Wearing their full-dress uniform complete with busby hats, the Irish Guards put on a memorable show right in front of the Queen's London residence at Buckingham Palace.
Duchess Kate released a stunning birthday portrait of Prince George
Royal fans went wild in the comment section with one writing: "How lovely! Happy Birthday to HRH Prince George!", whilst a second penned: "Love this SO MUCH! Happy 9th birthday Prince George!"
Impressed by the touching tribute, a third fan added: "How cool to have the @IrishGuardsBand play at your birthday!!", and a fourth remarked: "Such a beautiful and thoughtful gift, I'm sure Prince George loved it."
Prince George is the third in line to the throne
The Queen's musical-themed gift comes after Prince George's mother, Kate, released a stunning new birthday portrait of the young royal. To mark the special occasion, the Duchess of Cambridge shared a candid snap of her eldest beaming at the beach. Wearing a light blue polo T-shirt, George appeared to be in high spirits as he enjoyed his summer family holiday.
Many observant fans couldn't help but note Prince George's striking resemblance to his father the Duke of Cambridge. "Happy Birthday, what a lovely smile just like his dad's!" wrote one, whilst a second added: "He looks more and more like Prince William! Happy Birthday Prince George - hope you have a fantastic day."
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