Couple Jason Segel and Michelle Williams with Busy Philipps soak up some sun in Cancun, Mexico on January 2, 2013. Credit: MiamiPIXX/SBMF/FAMEFLYNET PICTURES

Boyfriend and BFF beach vacation!

Michelle Williams was photographed enjoying a tropical vacation Wednesday, Jan. 2 in Cancun, Mexico, with boyfriend Jason Segel and pregnant BFF Busy Philipps. The pals went for a stroll on the beach together to soak up some rays.

The Academy Award nominated actress, 32, debuted her toned beach body in a sexy black bikini, which she matched with a fedora and shades. Williams also styled an opened blue shirt to protect her skin somewhat from the sun. Segel, 32, whom she began dating in March, followed closely behind in a dress shirt, shorts, fedora and shades.

The couple was spotted at Cancun Airport on Dec. 27, and an eyewitness tells Us Weekly that Williams' daughter Matilda, 6, was with them. "They were really cute and just playing around together," the source told Us of Segel and Matilda. "Michelle was smiling and watching them." 

Cougar Town actress Philipps, who is expecting her second child with screenwriter husband Marc Silverstein, proudly showed off her baby bump in a skimpy red string bikini while joining the two for a walk. See more pictures from their tropical trip.

The expectant star, 33, who is already a mother to daughter Birdie, 4, told Us last month that she's looking forward to award season.

"The good thing about being pregnant is that I don't have to worry about sucking it in or dieting!" she said of walking the red carpet. "Lord knows there's no last minute body wraps to lose five pounds. Because what, you're gonna say I look fat? I don't think so!"