A teacher found a 101-year-old letter written by the Queen Mother being used as a bookmark.

The 59-year-old from Brighton found the thank you note tucked in a second hand book and has decided to sell it at auction.

It is dated January 27 1923 and followed news of the then Lady Elizabeth Bowes-Lyon’s plans to marry Prince Albert, the future King George VI.

Buckingham Palace announced the couple's engagement on January 15 1923 after his third marriage proposal was finally accepted.

The Argus: The Queen Mother's thank you letter and envelopeThe Queen Mother's thank you letter and envelope (Image: Hansons/SWNS)

She rejected the then Prince Albert twice due to fears about the impact of royal life.

The letter was sent to Mrs Carmichael of Downfield, Dundee, Scotland, together with a photograph of the royal.

Lady Elizabeth apologises for the "short note" and jokes about having so many thank-you letters to write "my hand has almost given out!"

The note was discovered by chance by the seller’s grandmother. It was tucked inside a second-hand book.

The seller, a 59-year-old teacher from Brighton, said: “It was being used as a bookmark. It was passed on to my mum, who sadly died in 2019, then it became mine.

“It would have been purchased in Aberdeen in the late 1920s I believe. My family originate from there. Having said that, my great grandma was from Dundee where she worked in the jute mills, so that’s also a possible link.”

The letter, on “17 Bruton Street, WI” letterhead, was part typewritten and part handwritten.

It says: “Dear Mrs Carmichael,

“Thank you so much for your kind letter of congratulations which I much appreciate.

“Of course I remember the Garden Fete at Downfield.

“You will forgive only a short note I know, but I have more letters to answer than I can manage. (Handwritten) And also this typewritten letter, but my hand has almost given out!”

It is signed Elizabeth Lyon.

A photo found with the letter shows the Queen Mother in her early 20s, possibly at Downfield Fete, Dundee, with Mrs Carmichael.

The note is set to fetch up to £600 but could sell for far more when it goes under the hammer at Hansons Auctioneers on Monday.

Hanson’s paper and books expert Jim Spencer said: “What an extraordinary discovery to make. I have no doubt it would have been a treasured possession.

“Aside from its importance as a royal memento, an informal photo was pinned to it, possibly showing Mrs Carmichael with Elizabeth.

“The original envelope was retained, too, which suggests it was treasured by Mrs Carmichael.

“Perhaps she placed it inside a book to keep it flat and, over time, mislaid it.

“This fascinating letter shows how the power of love circulates through all of our lives, even in royal circles."

Prince Albert, Duke of York, vowed he would marry no other woman despite having his proposal rejected. He first proposed to Elizabeth in 1921 but she turned him down, “afraid never, never again to be free to think, speak and act as I feel I really ought to”.

The Argus: A portrait of Queen Elizabeth Queen MotherA portrait of Queen Elizabeth Queen Mother (Image: Wikimedia Commons)

Aware of Albert’s lovelorn situation, his mother Queen Mary visited the girl who had stolen her son's heart.

She became convinced Elizabeth was "the one girl who could make Bertie happy", but refused to interfere.

At the same time, Elizabeth was courted by James Stuart, Albert's equerry, until he left the prince's service.

In February 1922, Elizabeth was a bridesmaid at the wedding of Albert's sister, Princess Mary, to Viscount Lascelles. The following month, Albert proposed again - and she refused again.

Eventually, in January 1923 Elizabeth agreed to marry Albert, despite her misgivings about royal life.

The Argus: Wedding of George VI and Elizabeth Bowes-LyonWedding of George VI and Elizabeth Bowes-Lyon (Image: Wikimedia Commons)

The couple married on April 26 1923 at Westminster Abbey.

Her reign as Queen of the United Kingdom and the Dominions of the British Commonwealth stretched from December 11 1936 to February 6 1952 as the wife of King George VI.

When he died aged 51, she was viewed as the matriarch of the British Royal Family and was active in public life until a few months before her death in 2002 at the age of 101.