First we noticed that some of our favorite trend-setters chose off-white fuzzy coats to transition into spring. Then on the red carpet hot young stars showed off their enviable curves with sexy cut-out waistlines. Looks like these fashionistas are ready for warm-weather dressing!

rachel bilson sienna miller rosie huntington whiteley white fuzzy isabel marant coat jacket

Photos: Fame Pictures | WENN | Bauer-Griffin

FUZZY FASHIONS:

Rachel Bilson kept casual for a business meeting in a wool Grammy Label sweater. Not only did the starlet look good, she was also doing good: proceeds of sales from the line benefit multiple charities! She paired her topper with boyfriend jeans and accessorized with black Ray-Ban sunglasses and a matching black handbag.

Sienna Miller was snapped by photogs in London wearing an aztec-printed frock and a seriously cozy Isabel Marant coat. The actress was seem leaving the Theatre Royal Haymarket after she performed in "Flare Path." We love the mix of textures and patterns and the addition of funky jewelry.

Boho babe coming through! Rosie Huntington-Whiteley was wandering around with her beau Jason Statham in West Hollywood wearing a sheer maxi skirt with the same fuzzy jacket as Sienna. She paired her layered look with a Rag & Bone "Kingsley" hat, Ferragamo envelope handbag and oversized shades.

crystal renn Shenae Grimes anna paquin black dress cut out waistline

Photos: Getty Images (2) | FilmMagic

Crystal Renn wore an attention-grabbing Zac Posen frock to the 8th Annual New Yorkers For Children Spring Dinner Dance, "A Fool's Fete," in NYC. The model was accompanied by Posen as her date, and we must say, that dress flaunted her figure! Gold chandelier earrings and bold red lip completed her over-the-top glam look.

Anna Paquin sunk her teeth into the cut-out trend with a Cushnie Et Ochs dress with chrome bars at the waist. The star of "Vampire Diaries" added a black python clutch and Brian Atwood pumps to walk the red carpet for the premiere of "Scream 4"

"90210" actress Shenae Grimes chose an American Gold Voodoo You Do dress from the Spring 2011 collection for the College Television Awards. She accessorized her fringe-trimmed frock (and sexy cut-out waistline) with her latest obsession -- a temporary black heart tattoo on her right cheek to show support for the Japan disaster victims as part of her Spread the Heart Movement.

For more celeb copy cats, check out last week's trends.

And click through this gallery of celebrity music festival fashion!