Fashion Faceoff: Pippa Middleton vs. Emmy Rossum

The world has closely watched what Pippa Middleton has worn since we met her.

This week, the younger sister of Kate Middleton, otherwise known as the Duchess of Cambridge, stepped out in the same sheath that we'd seen starlet Emmy Rossum sport days earlier.

What they wore: Tabitha Webb's Breast Cancer Summer Blossom dress, which, before it sold out, was $391.88.

[Related: Fashion Faceoff: Jennifer Aniston vs. Kate Moss]

When they wore it: The 29-year-old royal in-law donned the dress at the Waitrose Summer Party at the Natural History Museum in London on Wednesday. Meanwhile, Rossum, 26, wore the dress while strolling through Beverly Hills last week.

How they styled it: For Middleton, a pair of peach heels, a nude clutch, and elegant gold jewelry were perfect. Rossum, who wore sandals, added fun accessories by way of a big red bag and a long chain necklace.

[Related: Kate Middleton Shares Secrets of the Royal Nursery]

Judge's scorecard: Both win props for wearing a dress for a good cause — 30 percent of the purchase price goes to the CFDA's Fashion Targets Breast Cancer — which is always in style. While Middleton was lovely as always, do you think she looked a little too sweet?

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