Molly Sims relied on celebrity trainer Tracy Anderson and sessions of Bikram yoga to slim down in the 10 months since welcoming son Brooks, but now that the model and jewelry designer is back to her pre-baby weight, she finds it hard to slip out of the workout clothes she came to love while losing weight. "I have to force myself to get out of my yoga clothes," Sims admitted to Us Weekly at an April 25 event to promote Hudson jeans in L.A.'s Brentwood neighborhood.

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Modeling for Sports Illustrated before having Brooks, Sims, 39, says her style has suffered somewhat since she's become a mom. "I think I'm a little less trendy than I used to be," admits Sims, who wed movie producer Scott Stuber in September 2011 and gave birth to Brooks in June 2012. "I kind of stick with a style and go with it . . . [but I'm] definitely wearing more comfortable clothes."

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Calling Hudson jeans her go-to wardrobe staple ("I've been wearing them for 10 years," she tells Us), Sims admits that her passion for fashion is renewed every time she makes a trip back to the East Coast, where she began her modeling career. "I still love dressing up, and my boho chic, classic thing I do," explains the star. "I sometimes need to go to [back East] to have it refreshed."

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Speaking of her son Brooks, Sims couldn't help but share some of his latest milestones with Us. One major recent highlight for the little guy: He took his first step on April 24! "He took one step. I'm like, 'Come here!' He did it," beams proud mom Sims. "Everything is new and it's so fun to watch him -- it brings me so much joy. I have to say it's the most content I've ever been in my life."

This article originally appeared on Molly Sims on Her Post-Baby Style: "I Have to Force Myself Out of Yoga Clothes!"