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Ashlee Simpson (in Roberto Cavalli) and Minka Kelly (in J Brand) struck a pose at the  opening of Marquee at The Star in Sydney. “Ladies night at @MarqueeSydney with @Minkakelly @k8herrera @lolozelman. It’s gonna be a fun night!! #marqueeSydney,” Simpson Tweeted. Click through the gallery to see Carrie Underwood, Brooklyn Decker and more stars at last weekend’s hottest parties.

Kourtney Kardashian and Ashlee Simpson headed to Hollywood to kick off Caesars Entertainment’s “Escape to Total Rewards,” a series of simultaneous concert events in four cities. “Im Escaping w/ @Total Rewards Lil Wayne & @CeeLoGreen tonite @ Hollywood & Highland!“ Kardashian tweeted. Click through the gallery to see Jennifer Lopez, Salma Hayek and more stars at last night’s hottest events.

Ashlee Simpson and Vincent Piazza celebrated Valentine’s Day at New York City’s Dream Downtown Hotel, where the couple checked out a performance from Band of Horses at Rag & Bone’s Fashion: Take Note party. Simpson wore a sparkly black dress and a striped clutch for her date night, while Piazza bundled up in a camel coat and striped tie. See more stars at last night’s hottest parties in the gallery!

We couldn’t help but notice that many of the most stylish ladies in Hollywood have been keeping it short and sweet when it comes to their hair. Actually, make that short and sexy. Pixies seem to be the go-to style for these A-listers, including Halle Berry and Ashlee Simpson (top left).  Actresses Cate Blanchett and Emma Watson (bottom left) also dared to chop off their locks, leaving them with less hair but all the more wow factor. Click through the Gallery to see the ten pixie looks we can’t get enough of!

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