The singer, who split from husband Marc Anthony back in July, was in Kauai, Hawaii, on Thursday with Casper, 24, and her twins, Max and Emme, 3.
A source told Us Weekly the toddlers enjoyed the dancer’s company.
“Casper was great with the kids. He was twirling them around and doing flips with Emme and she seemed very comfortable with him,” the source said. “Jennifer got a chance to sit back and relax while Casper took over and played.”
In related Jennifer news, on Friday, FOX released a first look at Season 11 of “American Idol,” which she returns to for a second season in January.
Click HERE to watch the sneak peek!