Charles Spencer would have been filled with pride watching the Cambridges take centre stage at the Queen's Platinum Jubilee celebrations.
As Princess Diana's younger brother, Charles is a maternal uncle to Prince William and Prince Harry and has no doubt delighted in watching their families grow over the years.
WATCH: Princess Charlotte corrects Prince George's posture during National Anthem
William and Kate's three children, Prince George, Princess Charlotte and little Prince Louis, took on a significant role throughout the celebrations, including making their carriage debut at Trooping the Colour, and sitting in the front row for the Party at the Palace.
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It prompted a number of royal fans to note a striking similarity between Charles and his nephew's eldest son, Prince George.
Fans rushed to social media to comment on the likeness, with one noting: "Definitely a Spencer, just like his papa." "I think he looks like Charles!" another wrote, "Even the hairline!"
Fans went wild over the likeness between Charles Spencer and Prince George
"Have always thought he looks so much like Uncle Charles!" a third shared, while a fourth suggested: “"George is Spencer, Charlotte is Windsor and Louis is Middleton...all kind."
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Prince George and his siblings charmed the world with their sweet appearance over the four-day holiday.
The Cambrudge children joined the Queen on the balcony of Buckingham Palace
Princess Charlotte shared an adorable moment with her older brother during the closing moments of the Platinum Jubilee Pageant on Sunday when the young royals joined the Queen on the Buckingham Palace balcony.
READ: Hilarious moment between Prince George and Princess Charlotte you may have missed
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Her Majesty was greeted with enthusiastic cheers from the crowd and a rendition of the national anthem, after which a loud smoke cannon went off, prompting an adorable exchange between George and Charlotte.
Prince George enjoying the Party at the Palace with father Prince William
Charlotte, seven, can be seen flinching after the cannon went off, prompting George, eight, to turn to her and say, "That made you jump," to which she replied, "That made me jump!"
Fans also went wild over the footage showing Prince George singing Sweet Caroline along with his father during the star-studded party outside Buckingham Palace.
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