Olivia Wilde worked her toned body in a tangerine bikini in Hawaii on Saturday, Dec. 12. Credit: AKM-GSI

One hot mama! Olivia Wilde flaunted her taut and toned bikini body while vacationing in Hawaii with her family — including fiancé Jason Sudeikis and their 19-month-old son, Otis.

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On Saturday, December 12, the Meadowland actress, 31, modeled a tangerine two-piece with a halter top and cheeky bikini bottoms — all the better to show off her gorgeous frame. The brunette beauty also added a floppy hat and a striped towel as a sarong.

After a midday break from the beach, Wilde, who welcomed Otis in April 2014, made a quick change into a slate swimsuit, covered up by a sheer white top with tassels. She also rocked an underwire bra top and bottom in "Rainbow Multi" by Mara Hoffman that Sunday.

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The beauty even took to the high seas for a little paddleboarding action, dressed in a printed tank and square shades.

Wrapping up the weekend, the House alum took to Instagram to share a snap from her travels that featured Otis staring out at the ocean — butt-naked! Appropriately, she captioned the pic, "Naked Cowboy."

Naked Cowboy.

A photo posted by Olivia Wilde (@oliviawilde) on