Kristin Cavallari's boyfriend is apparently full of surprises when it comes to love.

NFL star Jay Cutler not only surprised the former Laguna Beach and The Hills star with a spontaneous vacation to Cabo San Lucas this past holiday weekend, but he also unexpectedly proposed during their trip, Us Weekly reported Tuesday.

"She is so excited and completely blind-sided," a source told Us of the newly engaged 24-year-old reality TV star. 

"They've been celebrating all weekend; Kristin told her girlfriends. Kristin told her girlfriends on Monday."

Cavallari and the 27-year-old Chicago Bears quarterback have reportedly been dating for eight months and met through Giuliana Rancic last August.

"You know who I set up? Kristin Cavallari and Jay Cutler," the Giuliana & Bill star and E! News host told Us in February.

"I knew them both for awhile and introduced them and they went on a date. Now they're dating."