Rare Princess Diana letters to her personal secretary to be auctioned off

Letters written by the late Princess Diana to her personal secretary, Jane Parsons M.B.E, are going to be auctioned off in April.

According to Vanity Fair, the contents of the correspondence reveal an “intimate glimpse into the marriage” between Prince Charles and the Princess of Wales.

In one of the letters, dated August 15, 1981, Diana writes from her honeymoon on Royal Yacht Britannia-crested paper: “The honeymoon was a perfect opportunity to catch up on sleep…”

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Other letters up for auction include a glimpse into Diana’s life as a new mother at the age of 20, after Prince William was born in 1982.

Diana wanted to ensure that her staff was not feeling “exhausted, overworked and underpaid” after William’s birth.

The letters revealed William received 4,500 presents in celebration of his birth, leaving Diana to reply with a total of 24,000 thank-you notes.

Items up for auction include a typed list of wedding gifts, dried flowers from the Princess’ wedding bouquet, letters written during the couple’s honeymoon on the Royal Yacht Britannia, thank-you letters, Christmas cards, photographs and invitations to numerous Royal events.

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Letters sent by Diana – including one in which she described a young Prince Harry as being “constantly in trouble” while at boarding school – sold for thousands of pounds at an auction in January.

WATCH BELOW: New letters written by Princess Diana to be sold at auction

1:10 New letters written by Princess Diana to be sold at auction

The six handwritten notes were sent to Cyril Dickman, a former head steward at Buckingham Palace, during the 1980s and 1990s.

Princess Diana and Prince Charles married at St Paul’s Cathedral in July 1981, before separating 11 years later in 1992 and finally divorcing in 1996.

She was fatally injured in a car crash on August 31, 1997, in the Pont de l’Alma road tunnel in Paris. This summer will mark the 20th anniversary of her death.