Jennifer Lopez may have had a fan girl moment in Aspen, Colo. On Friday, December 27, the "Get Right" singer, 55, was seen partying it up at the bar inside the celeb hotspot Kemo Sabe alongside Yellowstone star Kevin Costner after her estranged husband,

Affleck and Lopez have been a steady presence in the lives of each other’s kids in the last few years, so it makes sense that they would make the effort for Affleck’s three kids: Violet, 19, Seraphina, 15, and Samuel, 12 and Lopez’s two kids:16-year-old twins Max and Emme.

“Ben gifted Jennifer with the book because she’s a fan, plus her Super Bowl bodysuit was inspired by Marlon Brando,” a source said of Affleck's sweet gesture. “The gifts were mostly for each other’s kids, but they did exchange a few small things for each other as well."