Charles, 9th Earl Spencer, has long delighted his followers by sharing old photographs of his late sister, Princess Diana, as well as images of the Spencer family's ancestors.
And one recent Twitter post sparked a big reaction, with many seeing the likeness between Charles's grandfather, Albert, 7th Earl Spencer, and Charles's nephew, Prince William, when they were children.
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Sharing a sepia-toned photograph to his social media account, Charles wrote: "Love the family photographs I find here at Althorp. My grandfather (left), my great-aunt Lavinia (middle) and my great-uncle Cecil, about to set off for a fancy dress party in c.1902."
Charles shared a photograph of his late grandfather
Charles's Twitter followers were quick to comment on the similarities, with one writing: "Wow your Grandfather and the Prince of Wales are the absolute image of each, the Spencer Genes."
"I can see William in the boy on my left. Love these old photos," another said.
A third person wrote: "This is so lovely. I see Diana and William in your grandfather."
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Prince William in 1995
The Earl has been custodian of Althorp House in Northampton since the death of his father, John, 8th Earl Spencer, in 1992.
He regularly shares updates about the Spencer family estate on his social media accounts, posting photos and videos of its beautiful grounds, priceless works of art and resident animals, including a peacock.
The Grade I listed residence where the late Princess Diana grew up has 90 spectacular rooms and is surrounded by 550 glorious acres of land. The Northamptonshire estate is also the royal's final resting place.
Althorp House
Prince Harry has remained close to his mother Princess Diana's side of the family. He described a more recent reunion with his uncle, Charles Spencer, in the epilogue of his memoir, Spare, recalling the moment he took wife Meghan to see his mother's grave at her childhood home, Althorp, near the 25th anniversary of Diana's death last year.
The Duke describes him and Meghan getting into a boat to row across to the private island on the estate which marks Diana's final resting place.
"Uncle Charles came down to the water's edge, gave us a little shove. We waved to him, and to my two aunts. Bye. See you in a bit. Gliding across the pond, I gazed around at Althorp's rolling fields and ancient trees, the thousands of green acres where my mother grew up, and where, though things weren't perfect, she'd known some peace."
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