It's no secret that Camilla Parker-Bowles had a difficult introduction into the British Royal Family. She and Charles initially dated in 1970 but she was not popular with Queen Elizabeth II. Royal historians say that this was due to the fact that she had dated other men before Charles. Historian Dr. Piers Brendon says 'It was absolutely vital to have on the throne someone who was a virgin; a future Queen must have no past.' According to these historians it was for this reason that Camilla was considered 'unmarriageable'.
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Now - amid claims that relations are still frosty between Camilla and the rest of Charles' family due to her failure to attend Princess Eugenie's wedding in October - a new documentary 'The Royal House Of Windsor' has revealed that Prince Philip slammed Charles' relationship with Camilla in a series of intimate letters to Diana in the early 1990s.
Take a look at the video above for the shocking contents of Prince Philip's letters...