Charles Spencer often shares updates on Althorp House with his loyal followers.
But this week, he had something a little different to pique their interest.
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Princess Diana's younger brother took to Twitter to share a historical mystery with fans – much to their delight.
Charles shared a post that linked to a BBC article which he captioned: "The mysterious doodles hidden in a 1,300-year-old book."
The article documents the discovery in an 8th-century book - a copy of the Act of Apostles from the Christian New Testament, which is now kept in the Bodleian Library in Oxford.
Charles shared a historical mystery with his fans
In 2022, researcher Jessica Hodgkinson at the University of Leicester decided to take a closer look and was surprised to find a hidden etching on page 18, just below the Latin text.
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It comes after it was revealed that Charles had had to turn down his sister Princess Diana's request following her divorce from then-Prince Charles in 1996.
© Photo: Getty ImagesCharles and Diana grew up together at Althorp
Charles grew up at Althorp alongside three older sisters, but due to laws around how hereditary peerages are inherited, he became the 9th Earl Spencer following the death of his father and gained ownership of the property.
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He offered Diana a place to stay at their childhood home, but it turns out he had the hard job of rejecting her request when it came to living arrangements.
© Photo: Getty ImagesCharles had to turn down his older sister's post-divorce request
In a BBC Radio 4 interview as reported in People Magazine, the Earl made a choice because he felt it was "the right decision for her" but he did admit that "she probably couldn't see it".
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He explained: "Diana had a lovely dream that she could live a normal life afterward. But the one house that she set her heart on in the park [at the family home of Althorp] was three bedrooms and 100 yards from the road. And it was just not possible. The police knew it wouldn't work.
© Photo: Getty ImagesAn aerial view on Althorp - including the island where Diana was laid to rest
"I offered every other property that was suitable on the estate. I really felt it was the right decision for her. But she probably couldn't see it."
The main property of Althorp has a whopping 90 rooms, and the Earl opens it up in the summer months for members of the public to tour various rooms.
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