It's hard to believe that former "Party Of Five" star Lacey Chabert is 30! The actress, who has also appeared in "Mean Girls," celebrated the milestone event at the Gallery Nightclub held at Planet Hollywood Resort & Casino in Las Vegas on Friday night.

Chabert officially turns the big three-oh today.

The actress looked dazzling in a tight black sequined dress with subtle splashes of color on it. She wore a couple of chunky rings, studded earings, and a thin bracelet. She partied with her friends, including Amy Davidson ("8 Simple Rules") and Ali Fedotowksy ("The Bachelorette.")

Chabert has also appeared in the films "Ghosts of Girlfriends Past," "Daddy Day Care" and "Thirst."

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