Nearly 20 years after Princess Diana's tragic death, a set of the royal's private letters about life with her two sons, Prince William and Prince Harry, have resurfaced.

Beginning in the mid-1980s, Diana wrote a series of handwritten notes to former Buckingham Palace steward Cyril Dickman. After Dickman's 2012 passing, his grandson uncovered the letters and is now selling them at auction.

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"Dear Cyril, it was so very kind of you to have sent us such a lovely card, on the arrival of our small son, [Harry] — we both were greatly touched by your thoughtfulness and enormously appreciated it," Diana began one note following the September 1984 birth of her second child, according to the Cambridge News.

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Diana, William and Harry in October 1985.

"William adores his little brother and spends the entire time swamping Harry with an endless supply of hugs and kisses, hardly letting the parents near!" she continued.

"The reaction to one tiny person’s birth has totally overwhelmed us and I can hardly breathe for the mass of flowers that are arriving here!" Diana wrote.

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Years later in 1992, Diana wrote Dickman again to update him on William and Harry, then aged 10 and 8, respectively. "The boys are well and enjoying boarding school a lot, although Harry is constantly in trouble!" she wrote, according to Yahoo.

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Diana with William and Harry in April 1993.

According to a representative from the auction house selling Dickman's letters from Diana, the former Buckingham Palace employee was a beloved staff member and friend of the royal family.

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"Cyril, who died in 2012, was head steward at Buckingham Palace for over 50 years… He was a favorite of every member of the royal family, as is evident by the variety of cards and letters he received," Lisa Freeman-Bassett of Cheffins auction house told the Cambridge News.

Diana — who shared sons William, now 34, and Harry, now 32, with husband Prince Charles — sadly passed away at age 36 in an August 1997 car crash.

Click through the gallery below to see Diana’s cutest photos with William and Harry!