HBD, HRH! Queen Elizabeth turned 91 on Friday, continuing her reign as the oldest living monarch.
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Though Her Majesty celebrates her birthday at the Trooping of the Colour celebrations in June, she enjoyed a beautiful rendition of "Happy Birthday" played by the Irish Guards Band during the Changing of the Guard at Buckingham Palace.
The royal social media accounts also paid tribute to the milestone day, with the Kensington Palace account writing, "Wishing Her Majesty The Queen @theroyalfamily a very Happy 91st birthday today!" alongside a photo taken from last year's Trooping the Colour celebrations.
The Royal Family account shared a rare throwback photo of the Queen at age 2, writing, "Happy Birthday Her Majesty! As The Queen turns 91 years old today, we wanted to share a rare photograph of Princess Elizabeth (as she was known then) as a young child. The two year old princess is pictured waving from her a carriage as it drives through London in 1928."
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As the Queen enjoys her birthday festivities, her grandchildren continue their hard work advocating for mental health awareness.
For more on their latest initiatives, watch the clip below!