Prince Charles
Britain's Prince Charles was "fascinated" by his newborn sister Princess Anne, according to a letter written by the Queen in 1950.
In the note, addressed to the monarch's friend Mrs Tanner, the 87-year-old royal admitted Charles, 65 - who was two years old at the time - treated his baby sister with "great care" and she couldn't wait until they were old enough to "play together."
Queen Elizabeth then went on to tell her pal that Princess Anne - who is now 63 years old - was nothing like her older sibling and she was intrigued to find out whether she would turn out like herself or her husband Prince Philip, whom she married in 1947.
She wrote: "The baby is quite unlike her brother, so it will be interesting to see whom she will take after when she is older."
The two-page letter, which was written in fountain pen, will now, 64 years after it was written, go on sale for £600.
The note is dated 3 September, 1950 - 19 days after Anne's birth on August 15 - and came from Clarence House in London, where she lived with Philip before becoming Queen two years later.
Richard Davie, of International Autograph Auctions, said it was rare to find such an emotional letter written by Her Majesty.
He told the Daily Mail newspaper: "The Queen has been a prolific letter writer over the years but most recipients have kept their letter.
"Most letters are not going to be of this nature and it highlights really well the Queen's maternal instincts, which makes it an interesting read."
Queen Elizabeth and Prince Philip also have sons Prince Andrew, 53, and Prince Edward, 49.
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