PIC: New Mom Jessica Simpson Shows Off Leaner Legs in Denim Shorts

Jessica Simpson celebrates her boyfriend Eric Johnson's birthday with friends and family on September 20, 2012 in Santa Monica, California. WENN.com

Jessica Simpson is slowly but surely getting her pre-baby body back!

The Weight Watchers spokeswoman, 31, showed clear signs of progress while celebrating her fiance Eric Johnson's 33rd birthday in Santa Monica, California, September 20. Wearing denim shorts and red platform heels, the "I Wanna Love You Forever" singer unveiled her leaner legs at Shutters at the Coast Cafe.

In recent weeks, Simpson has been open about her struggle to shed her post-pregnancy pounds. "I'm not a supermodel. My body is not bouncing back like a supermodel. I'm just your everyday woman who is trying to feel good and be healthy for her daughter [Maxwell, 4 months], her fiance and herself," she told USA Today September 4. "I feel like everybody can do what I am doing."

"Nobody wants to talk about their weight. For me, I have had to come to a place where I am comfortable with myself," the Texas native added. "I'm a mom now, and get to be a role model for this beautiful little girl."

Luckily, Simpson has the support of Johnson, whom she began dating in the spring of 2010. "The fact that he loves me the way I am right now — we're set. He knows I want to feel better in my skin."

Though Simpson is following Weight Watchers' PointsPlus program, she said she doesn't "believe in completely depriving yourself. . . I'm a woman who wants her chocolate. I allot myself a fun-size bag of M&Ms. I eat one of those, and my craving is satisfied. I don't need the whole bag of M&Ms."

The new mom is also working with personal trainer Harley Pasternak about four to five times a week. "I've lost weight every single week," Simpson told USA Today.

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