Justin Bartha Engaged to Lia Smith

Justin Bartha has a reason to celebrate!

The Hangover Part III star, 34, is engaged to personal trainer Lia Smith, PEOPLE has confirmed.

“They’re very happy,” a source says of the pair, who was first publicly linked this past New Year’s Day when they were photographed in Smith’s native state Hawaii, where they were “very cute” and affectionate, according to an onlooker at the time.

5 Things to Know About Crystal the Hangover Monkey

The biggest comedy of the summer season includes a few familiar faces – and one you might not know is so familiar. Here are five things you might not know about Crystal, the scene-stealing monkey of Hangover 2:

Ken Jeong Got Wife's Okay Before Getting Naked in The Hangover Movies

Ken Jeong donned his birthday suit in The Hangover and he does it again in The Hangover Part II. But before he displayed his body, he asked for approval from one person – his wife.

“I got her permission. I’m not stupid,” the actor, who plays flamboyant, foul-mouthed gangster Leslie Chow, told PEOPLE at the film’s Los Angeles premiere this week. “I ran it by her before I ran it by [director] Todd Phillips.”