Clasos.com.mx / Splash News
The engaged couple was photographed arriving on Friday, Dec. 27 in Mexico, a traditional destination for the duo this time of year.
The We're the Millers starlet, grinning as she made her way around the airport, looked casual chic for the warm temperatures, wearing a green blouse, skinny jeans, nude wedges, aviators and her beautiful engagement ring. Theroux sported a dark gray sleeveless T-shirt, black pants and black boots.
The couple seemed "happy, relaxed and looking forward to their break," according to a source. Several friends joined Jen and Justin and the group is all staying at the same resort while they ring in 2014.