Charles Spencer is penning a memoir about his childhood, it has been revealed.
According to The Daily Mail's Sebastian Shakespeare, the book has already received praise from the Earl's wife, Countess Spencer.
She told the newspaper: "I've just finished reading the book my husband is writing about his childhood. It's very moving."
The title and its publication date are yet to be confirmed.
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Charles grew up at Althorp House in Northamptonshire, with his three elder sisters, Sarah McCorquodale, Jane Fellowes and Diana, the late Princess of Wales - pictured above with Charles in 1968.
The author, 56, was born to John Spencer, the 8th Earl Spencer, and Frances Shand Kydd, before their marriage ended in divorce when he was four years old.
Charles is already an established author and has written several books, including the Sunday Times best-seller, Blenheim, Battle for Europe.
He has been custodian of Althorp House since the death of his father in 1992, and has helped to restore the Grade I stately home, including a major renovation of the roof and stonework in 2009.
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Althorp House, the Spencer family estate
Charles 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.
Meanwhile, the dad-of-seven has very close links to the royal family, not only for being Princess Diana's younger brother and therefore Prince William and Prince Harry's maternal uncle. He is also the godson of the Queen.
His father had worked as an equerry for King George VI and a young Queen Elizabeth. The Queen herself had been guest of honour at John's wedding to Frances Rocheg at Westminster Abbey on 1 June 1954.
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