By Adam Carlson
Updated March 20, 2016 at 03:39 PM EDT
Credit: Anthony Harvey/Getty Images

Friends, family, and a really talented boyfriend – what else does Taylor Swift need for a great Friday night?

The pop star, 26, hit up Caesars Palace’s OMNIA Nightclub, in Las Vegas, alongside Karlie Kloss, to celebrate the 21st birthday of Kloss’ twin sisters, Kimberly and Kariann. They were joined by Swift’s younger brother, Austin, and several members of Haim.

Spinning the soundtrack of their night was Swift’s boyfriend, Calvin Harris, OMNIA’s resident DJ.

The evening’s itinerary included the usual high-energy hi-jinks: singing, dancing and lots of photos; and the group crowded the DJ booth in celebration.

Swift has been doubling as a jet-setter this week: She and Harris, 32, who recently celebrated their one-year anniversary, just returned from a romantic, beach getaway.

And on Friday, Swift surprised several sick kids at the opening of a new multimedia studio at Nashville’s Monroe Carell Jr. Children’s Hospital at Vanderbilt University.