Aniston, 43, and fiance Theroux, 41, started soaking up the sun in Cabo since before Christmas. But the couple was joined by pals John Krasinski, Emily Blunt, Jimmy Kimmel and Molly McNearney.
"They spent the afternoon lounging around and having drinks [at Jen and Justin's house]," an eyewitness told Us Weekly of the friends' gathering on Dec. 27. "They seemed to all be really good friends and comfortable around each other. Emily was lying in John's lap, and Jen had her arms around Justin. They were there all afternoon until sunset, laughing and having great conversation."
Clooney and Keibler also made the trip to Cabo. According to The New York Post, the Oscar-winning actor, 51, and his gorgeous girlfriend, 33, enjoyed a private dinner with Aniston and Theroux at El Dorado resort.
Keibler has been documenting her Mexican getaway on Instagram. The actress, model and former WWE wrestler was also joined by pals Dave and Odette Annable. "Reunited and it feels so good," Keibler tweeted with a photo of them hugging.
Keibler and Phelps, 27, kicked off the holiday celebrations a little early with a game of beer pong. Keibler tweeted a photo of herself posing with her beer pong partner, writing, "Dominating. Team Baltimore. Geometry. Good times."