Credit: Splash News Online

A few years ago, Nicole Richie shocked fans by looking frail in a bikini.

For her bachelorette bash in Mexico over the weekend, she flaunted a fuller, healthier bod. See more pics of Nicole's Mexican vacation.

Earlier this year, Richie -- who turns 29 Tuesday -- denied ever having an eating disorder.

"I felt it was a little unfair to say someone has an eating disorder when they don't," she told the March U.K. issue of Marie Claire. "It's extremely insulting and irresponsible. An eating disorder is serious and it's a disease. I don't think you can lightly say someone has a disease unless they are openly telling you that they do."

At the time, Richie -- mother to daughter Harlow, 2, and Sparrow, 1 -- attributed motherhood to her shape. "I'm nursing and he's a big boy," she said.