Mila Kunis, 31, stepped out in Studio City, California on Tuesday, Nov. 25 in leggings and a long sleeve white shirt that revealed she had snapped back to her petite shape quickly following childbirth, reports Us Weekly.

Fiancée Ashton Kutcher, 36, accompanied his wife as she shopped at Ralph's grocery store. He wore a cropped sweater with skinny jeans.

While good genes could play a part, it is more likely the yoga classes the new mom attended from conception until the end of her third trimester made reclaiming her slender figure possible. Even on her birthday, Kunis went to maternity yoga class in Los Angeles. That's dedication.

The Golden Globe nominee is also "back to doing yoga and working out several times a week," a source told Us Weekly. She's also taking walks around her neighborhood with newborn Wyatt.

After giving birth to beautiful baby girl Wyatt Isabelle Kutcher on Oct. 1, the first-time mom was spotted on Oct. 17 in Los Angeles behind the wheel of the couple's new Lexus sedan. Newborn Wyatt reportedly was secured in a car seat in the back. The actress reportedly looked tired that day.

Kutcher, 36, surprised everyone on "The Talk" when he said that he and Kunis have not hired a night nurse or nanny since bringing baby Wyatt home. The proud parents want to care for their daughter themselves.

"We decided right away that we didn't want to have a nanny or a night nurse, and we're lucky enough that we have jobs where we can stay home and take time off where we need to," Ashton told the "Talk" hosts.

Kutcher said the couple decided before childbirth that they would not hire anyone to help raise their baby. The first-time parents are ready to experience the joys and challenges of caring for one-month-old Wyatt.

The end of October, the actor explained on TBS' "Conan" how the couple chose Wyatt's name on the way to a Lakers game. While Wyatt may seem a bit odd as a girl's name, the couple decided on the more traditional name "Isabelle" for the baby's middle name in honor of Kunis' grandmother.

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