Kate Beckinsale Rocks Amazing Bikini Body Alongside Lookalike Daughter

Kate Beckinsale shows off her bikini body in Mexico Clasos.com/Splash News Online

Great Kate! Kate Beckinsale and daughter Lily have been enjoying some R&R in Cabo San Lucas, Mexico — and in new poolside photos, the 39-year-old actress revealed the stunning rewards of her strenuous, butt-kicking work in action films like Total Recall and Underworld: Awakening.

PHOTOS: Hottest bikini bodies of the season

Wearing a black bikini top and skimpy white bikini bottoms on March 28, the sunglasses-clad British brunette showed off her flat abs and toned arms and legs. Also remarkable? The striking similarity between Beckinsale and 14-year-old Lily, her only child with ex Michael Sheen. One day earlier, Beckinsale chatted with Lily — who has her mother's porcelain skin, dark locks and delicate features — as she texted a pal in a lounge chair.

How does the nearly-40-year-old star maintain that jaw-dropping figure? It's not easy — particularly since she's not a huge fan of working out, and typically scales back in between training for her intense action roles.

kate beckinsale
Kate Beckinsale and her daughter Lily Mo Sheen hanging out poolside with some family members while on vacation in Cabo San Lucas, Mexico on March 27, 2013. FameFlynet

"I just can't make it part of my daily life. I go to the gym when I have to, and if I have to bulk up or slim down for a film, I will," she told ELLE UK. "I've recently got back into exercising four times a week. I run for half an hour at a time but never outdoors as I don't exercise in public. My gym's in my garage at home."

The stunner is also still adjusting to life as a parent to a teenager, she told Allure last year. "I haven't been embarrassing [to somebody] before, . . . I can't dance at a party where there are teenagers without [them] clearing the dance floor."

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