How Ashlee Simpson Dropped the Pregnancy Pounds

Ashlee Simpson-Wentz is back to her slim figure after giving birth

Ashlee Simpson-Wentz delivered son Bronx Mowgli in November -- and she's already back to her slim and sexy figure!

"After I had Bronx I lucked out," the actress/singer tells People magazine. "I mean, I'm 24-years-old, [I have] the genes from my mother and I did work out for three months," she added.

Ashlee stays busying on the set of her new show "Melrose Place" and she gets a hand from Bronx's grandparents while hubby Pete Wentz is on tour. Simpson-Wentz says her mom Tina and mother-in-law Dale are both "amazing" grandmas.