The Sight Of Kate Middleton Made Duchess Camilla 'Burn With Jealousy,' Says Royal Insider

If Princess Diana was a thorn in Camilla's side, Kate Middleton was a spear.

From the moment Prince William told the family that he was about to propose to Kate, the devious Duchess knew that if she was ever going to wear the crown she would have to reach deep into her bag of dirty tricks to undermine the charming beauty. Her fears that Kate would win the hearts of the British public and so impress the Queen that she'd bypass Prince Charles and make William king were not without merit.

"The truth is, the very sight of Kate made Camilla burn with jealousy from the beginning," a royal insider reveals. "She called her Kate Simpleton behind her back." There was no doubt that Kate was about to become the new People's Princess — the new Diana — and Camilla would cast herself as the evil stepmother."

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The Duchess was determined to make sure it would be a rocky road to the altar for Kate. And the knives came out in February 2011, when she and an unsuspecting Kate went out for a ladies' lunch at a posh London restaurant, under the guise of Camilla giving the bride-to-be advice on royal behavior and etiquette at the palace.

"William's wicked step mother absolutely humiliated the poor girl, making her feel like she's nothing but an uppity commoner who doesn't know her place," a royal insider said. Ironically, it was the Queen herself who facilitated the lunch date.

"Elizabeth stepped in to bring Camilla and Kate together to show a united front before the wedding," says the source. "Her Majesty saw William and Kate's nuptials as a new beginning for the monarchy — which is why royal insiders believed she felt her grandson should be the next King, not Charles."

But sensing that, Camilla used the date at Koffman's, a tony restaurant at the Berkeley Hotel, as an opportunity to tear into her new rival.

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"All eyes in the restaurant were on Camilla and Kate — it was a surprise to see them together," says an eyewitness at the eatery. "Looking back, it was a well planned trap. They could have had a secluded table away from the rest of the diners, but the Duchess of Cornwall chose one where they could be overheard."

According to sources, Camilla knocked back several glasses of red wine — and as the meal went on, her voice got louder and louder for all the patrons to hear.

"At one point, everything went virtually silent, except for the Duchess, who quite clearly said, 'Let me give you some advice young lady,' in a very condescending tone," says the eyewitness. "She was sneering."

Another source says Camilla deliberately flaunted her own blue blood to make Kate feel like a peasant out of her element. Camilla bragged that she was a baron's granddaughter, the source adds — and mocked the fact that Kate came from a nouveau riche family of airline workers.

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"Camilla told Kate that she must always remember her place — and common blood — around William's family," the source says. "She was trying to humiliate William's bride and make her cringe. She did a wonderful job." Kate — whose parents Carole and Michael Middleton met while working for British Airways and made millions selling mail order party goods — is proud of her family. But she was visibly shaken by the sudden attack — even though she maintained her dignity and kept a smile on her face.

Then, as an added twist of the knife, Camilla urged Kate to order the "divine" foie gras — a dish banned by Prince Charles because of the cruel way it's made from the fatty livers of force-fed geese.

Days later, poor Kate was ripped apart in the British press for ordering the dish. "It was a way for Camilla to diminish Kate in the eyes of public — and her own husband. The woman will stop at nothing to destroy William's beloved."

But the Duchess soon learned that Kate is nobody's fool and in spite of her relentless attacks, Kate would succeed in keeping Camilla's at arms length and marry the love of her life.

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"Kate's no hothead, but she can be stubborn if she's pushed into a corner," says a palace insider. "She will not be bullied — by Camilla or anyone else. The more Camilla tries to bully her, the more Kate will put her foot down and stand up to her."

But that would not stop Camilla from continuing her reign of terror.