Molly Sims and family spending Easter in Los Cabos, Mexico on March 30, 2013. Credit: / Splash News

Family fun South of the Border! Molly Sims and producer hubby Scott Stuber took baby boy Brooks to Cabo San Lucas, Mexico for Easter weekend. The model, actress and designer, 39, had plenty of bonding time with her 9-month-old on Easter Sunday -- playing her son (covered up with along-sleeve shirt and floppy hat) in the resort pool.

Former Sports Illustrated Swimsuit Issue model Sims was less concealed from the Mexican sun -- showing off her skinny, toned bikini body in a skimpy black two-piece and wrapping up in a floral Theodora and Callum scarf.

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Sims debuted her post-baby beach body last month on a girls' trip to Playa del Carmen, Mexico, where she helped celebrated a pal's birthday. The blonde Kentucky native has been frank about her fight to slim down after Brooks' June 2012 birth.

"I developed a thyroid condition during my pregnancy, so I didn't realize why I was gaining so much weight. So now I'm on thyroid medicine. My thyroid kind of shut down, so that really made it very difficult in terms of the weight loss," the Project Accessory told Us Weekly earlier this year. "It's been difficult, I'm not going to lie. I've had to exercise and keep a very, very rigid diet. I mean, it's the hardest thing I've done -- and I've modeled since I was pretty much 21 years old!"