Kristin Cavallari and Jay Cutler Are Engaged

By Jennifer Garcia

UPDATED 04/26/2011 at 10:20 AM EDT • Originally published 04/25/2011 at 11:15 PM EDT

Former Laguna Beach star Kristin Cavallari got one sweet surprise while on vacation in Mexico with her NFL beau Jay Cutler.



A source close to the couple confirms to PEOPLE that Cutler proposed over the weekend during their getaway in Cabo San Lucas.

"He surprised her with a quick trip to Cabo to ask her to marry him," the source says.

RELATED: Kristin Cavallari & Jay Cutler: 5 Things to Know About Their Romance

Cavallari, 24, who also appeared on The Hills, and Cutler, 27, the quarterback for the Chicago Bears, have been dating since last fall.

"I'm in love," she told PEOPLE earlier this year, "and it's been great."

Her rep couldn't be reached for comment.

RELATED: Kristin Cavallari Flashes Her Engagement Ring