Holly Madison Shows Off Slim Post-Baby Body Three Weeks After Giving Birth to Daughter Rainbow: Picture

Holly Madison arrives at Cirque du Soleil's 'One Night for ONE DROP' at Hyde Bellagio at the Bellagio on March 22, 2013 in Las Vegas, Nevada.  Steven Lawton/FilmMagic

That didn't take long! Less than three weeks after giving birth to daughter Rainbow Aurora, Holly Madison is back in red-carpet-ready shape. The new mom and former Playboy model, 33, showed off her sexy post-baby body at Cirque Du Soleil's World Water Day celebration on Friday, March 22.

Arriving at the Hyde Bellagio in Las Vegas, the Girls Next Door alum was radiant in a blue fit-and-flare frock, belted to show off her narrow waist. She paired the sweet dress with black heels and her usual super glam blonde curls.

Madison and boyfriend Pasquale Rotella welcomed their first child on Tuesday, March 5. "I couldn’t be more blessed to have such a perfect daughter and have never been happier than I am now!" she wrote on her blog shortly after Rainbow's birth. 

Defending her little girl's colorful moniker, she added: "There are a lot of smug haters out there who bag on my choice of a name, but I don't care about what they think. I want my daughter to be proud of who she is and learn to speak up and stand up for herself at a young age."

"I spent most of my life being a people-pleaser who worried about what other people thought or thought was cool," she continued. " And I don’t want that for her."

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