Kate Middleton, Camilla Gorge on “Naughty” Sweets on Store Visit with Queen Elizabeth

Kate Middleton, Carole Middleton and the Queen

Three Queens walk into a London department store . . .

On Thursday, Kate Middleton hit London department store Fortnum & Mason with stepmother-in-law Duchess Camilla and grandmother-in-law Queen Elizabeth. Arriving in the Queen's Bentley, all three women wore different shades of blue — Camilla in navy, her Majesty in eggshell blue, Duchess Kate in a fall-winter 2010 Missoni coat, accented by two daffodils to commemorate St. David's Day.

Although it was the trio's first official public duty performed en masse — part of the Diamond Jubilee schedule, celebrating the Queen's 50th year on the throne — Kate, 30, Camilla, 64, and Elizabeth, 85, were like three girls in, well, a candy store!

A source inside the shop reveals that Kate went straight to the chocolate counter (which she called "the naughty counter") in the newly-restored food hall and confessed to the staff, "Oh, I love chocolate. Yes. I think most girls like chocolate"

Prince Charles' wife Camilla, meanwhile, tucked into a bag of gourmet jelly beans nearby. "What a treat!" she cooed.

Queen Elizabeth, however, abstained from all sweets during the visit — but did join a tea party at the store with 150 staff members, and checked out a cake to commemorating the renaming of the store restaurant to The Diamond Jubilee Tea Station.

"They thoroughly enjoyed the visit," a source says. "Kate bought some Fortnum & Mason dog biscuits for Lupo."

During a plaque unveiling outside, "Kate was standing by Camilla the whole time, making sure not to get in the way of the Queen. She seemed a little quieter than usual, taking lead from Camilla the whole time."

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