full size Jennifer Aniston and Justin Theroux Make a Happy Couple

Jennifer Aniston and fiancé Justin Theroux are happier than ever  as their successful tree-trimming party this weekend can attest.

The couple  and Wanderlust co-stars  threw a holiday party at their Beverly Hills rental house on December 2, which has become an annual tradition for Jen.

Along with Jennifer's employees and their families, the festive shindig was attended by such famous faces as Demi Moore, Ben Stiller, Tobey Maguire, and Ellen DeGeneres and Portia de Rossi.

"The party was for both adults and children," a source tells People. "Jen loves having children around and she always has fun activities planned for them. While the adults mingled, the younger guests were able to color and play games."

"Jen always puts a lot of effort into planning her holiday party," the source continues. "It's a thank you party for her employees, and she always gives them thoughtful gifts. Jen always asks her celebrity friends for charity donations instead of personal gifts."

In other words, Jen is definitely no "horrible boss"!

full size Demi Moore Hospitalized
Credit: Jason Kempin/Getty Images

As for picking out the perfect evergreen, that is not something that Jen takes lightly. "For the second year in a row, she picked out a tree with [Justin]," says the source. "She seemed very excited and happy about the tree. [Justin] was very sweet to her and let her take her time to find the perfect tree. She found a beautiful one that she had delivered."

Meanwhile, the couple themselves "are doing really well together," adds the source. "Jen always seems so happy. Justin takes great care of her. ... They are both looking forward to a break. They had an intense fall with a lot of work."

Sounds like Jen and Justin are very far from ever having a "break-up." We're wishing them the best!

Source: People

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