Holly Madison's baby bump is getting bigger!

Currently 13 weeks along, the Girls Next Door alum, 33, showed off her growing pregnancy curves at the launch of Lucky Pet Products by Holly Madison during the SuperZoo 2012 Convention at Mandalay Bay Las Vegas September 11. Wearing pink peep-toes and a demure ivory dress, the buxom blonde played with several puppies while promoting her new line.

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When Madison exclusively shared the news of her pregnancy with the September 10 issue of Us Weekly, the ex-Playboy model said she hopes to one day "have six kids" with her boyfriend of nine months, party planner Pasquale Rotella, 38. She and her Las Vegas-based beau plan to wed "in a year," Madison added.

For now, Madison -- who split with Hugh Hefner, 86, in 2008 because he could not have kids -- is eagerly awaiting the arrival of her firstborn. "I can't wait to find out if it's a boy or a girl," she told Us.

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Though Rotella has been happily doting on her, Madison is careful not to use his kindness to her advantage. "I told him no food-craving runs in the middle of the night! No chocolate cake! I don't want to let myself go, then have a tough time getting back in shape," Madison explained. "I try to eat healthy for the baby -- I love vegetable and fruit smoothies. But my downfall is french fries. My excuse is they settle my stomach!"

This article originally appeared on Usmagazine.com: Holly Madison's Baby Bump Makes Red Carpet Debut