A selection of Princess Diana’s personal letters will be heading to auction.

London-based Lay’s Auctioneers has announced its upcoming auction, titled “Diana, The Private Correspondence of a Princess”, which is described as “an astonishing, confidential collection of 32 highly personal letters and cards written by the Princess of Wales to two of her closest friends.”

The sellers, Susie and Tarek Kassem, are described as “very close friends” of the late princess, with the letters said to “reflect the special and loving relationship they had with the most unique women that they had ever known.”

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While the Kassems are hanging onto the “more personal and confidential letters” they received from Diana, the 30-plus letters being auctioned are said to “illustrate Diana’s immensely warm and loving disposition in a charming and delightful manner.”

In addition, some of the letters are said to “touch on the enormous stress she was experiencing during periods of very public heartbreak, yet her strength of character and her generous and witty disposition shine through.”

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As for why the couple has decided to auction the letters, it’s because they don’t want to saddle their children with the “responsibility” of owning the letters, and will use proceeds of the sale “to support some of the same charities that were close to Susie’s and Diana’s hearts.”

The letters will be sold in individual lots at the auction house’s next antiques & interiors Sale, on Feb. 16.