Sofia Vergara has more than just the big 4-0 to celebrate.
The Modern Family actress -- who is currently enjoying a birthday extravaganza at a Mexico resort alongside 90 loved ones -- is now engaged to her on-again love Nick Loeb, a source confirms to Us Weekly.
The insider reveals Loeb popped the question during a visit to Chichen Itza, some Mayan ruins near the Rosewood Mayakoba resort where Vergara (and her massive group of birthday revelers!) are staying.
Wonderwall first broke the news of Vergara's happy news and pointed out that on Monday night, Vergara showed off a tell-tale diamond sparkler in a photo posted on her friend Fernando Fiore's Twitter.
The marriage will be the Three Stooges star's second; the actress wed Joe Gonzalez as a teen, with whom she has a son, 20-year-old Manolo. (She and Gonzalez divorced in 1993).
Vergara first met the politically active Loeb (who considered a 2010 run for Florida's state senate) at a Golden Globes party in 2008; the pair split ways after "fighting for a long time" in early May, though they reunited just a few weeks later.
"They have a crazy relationship," an insider explained of the duo's roller-coaster romance. "They break up and make up. They fight and make up hard!"