Kate Middleton Stuns in Daring Rose Gown and Ruby Encrusted Diamond Necklace Owned by Queen Elizabeth -- See t

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Kate Middleton just sported her most daring gown yet!

The mother of two showed off a bit more skin than usual while rocking a V-neck Marchesa gown at the state banquet for the visiting royals, King Felipe and Queen Letizia of Spain, at Buckingham Palace on Wednesday.

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The Duchess of Cambridge accessorized the gown's neckline with a ruby encrusted diamond necklace owned by Queen Elizabeth II. She also wore the Lover's Knot tiara, one of Princess Diana's favorites.

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The queen, meanwhile, went for a white ensemble, wearing a long satin gown by Angela Kelly and the Golden Fleece Order. She accessorized with a matching aquamarine tiara and necklace as she stood next to Queen Letizia, who went glam in a red off-the-shoulder gown and diamond tiara.

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Prince Charles, Camilla, Prince William and Prince Harry were also in attendance at the event, which was Harry's first official state banquet appearance in support of his grandmother. The event will also likely be Prince Philip's final public dinner, as his retirement from public duties will go into effect this fall. 

RELATED: Spanish Royals King Felipe and Queen Letizia Get Glam Reception by Queen Elizabeth and Prince Philip: Pics!

Middleton and her husband, Prince William, attended their first dinner for a visiting head of state in October 2015. See more in the video below. 

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