Britney Spears showed her support for children with an appearance at Jenny McCarthy and Jim Carrey's Snow Queen Vodka-sponsored fundraiser for Generation Rescue, an organization dedicated to researching autism, STAR reports.

Britney Spears shows her support for children

"Britney looked amazing — her hair and makeup were perfect and her body appeared toned — and she seemed very confident," a partygoer tells Star. "Her whole demeanor was calm, like she'd undergone a complete transformation."

"She was really well-behaved but didn't want to socialize," the eyewitness tells Star. She kept her distance from fellow VIPs Charlie Sheen and Brooke Mueller, Sarah Silverman, Rose McGowen, Cheryl Hines and Mekhi Phifer.

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