The 58-year-old has rarely posted on social media since the Queen's death on Thursday, but on Sunday, he shared a beautiful photo of her Majesty and Prince Philip with his father, who once served as equerry to King George VI and to Queen Elizabeth II.
In the black and white photograph, John Spencer could be seen with the royal couple in Australia, whilst on their 1953-4 Commonwealth Tour.
WATCH: The Queen's 70 year reign in pictures
Captioning the picture, Charles wrote: "The Queen & Prince Philip greeted by a huge crowd in Australia during their triumphant 1953-54 Commonwealth Tour.
"My father - who was HM’s Equerry then - sits in front of them in the Land Rover, next to the driver."
The photograph tribute was met with an outpouring of love on social media.
"What a beautiful photo for your family to cherish," one said.
Another wrote: "A lovely photograph and memory."
Charles' post comes days after King Charles III announced Kate will now use Diana’s title the Princess of Wales.
A short time after the announcement, Diana’s brother shared some kind words about the royal family.
Alongside a photograph of the Spencer family's ancestral home Althorp, he wrote: "We will keep the flag at @althorphouse flying at half-mast till after Her Majesty’s funeral."
A special photograph from Princess Diana's wedding day
The Earl also posted a photograph of the monarch in her coronation gown as a heartfelt tribute shortly after the news of the Queen's death was made public.
The official announcement about Her Majesty's death read: "The Queen died peacefully at Balmoral this afternoon.
"The King and The Queen Consort will remain at Balmoral this evening and will return to London tomorrow."
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