Taylor Swift & Nelly Perform for Karlie Kloss in the Hamptons

Best friends will usually buy each other small birthday gifts, share a hug and maybe post a picture on Instagram—Taylor Swift, however, is not your average friend. The singer went above and beyond in the Hamptons on Saturday when she performed a song with Nelly for her best friend Karlie Kloss’s big day.

Kloss, Swift and friends celebrated at an exclusive birthday party for oil Heir Mike Hess in East Hampton when the performance went down. Nelly and Swift performed his mega-hit single, “Dilemma.” Rocking a black mini skirt with a matching crop top, Swift belted out Kelly Rowland’s part of the song and showed off some sexy dance moves, while Nelly, dressed in white tee and matching white jeans, helped her along. Kloss and her party guests laughed and cheered (scroll down for the video).

A Victoria’s Secret Angel, Kloss, who turned 24 last Wednesday, August 3, has been named among Swift’s best friends since fellow Victoria’s Secret model Lily Aldridge introduced them about a year ago. In the months following their meeting, the pair have road tripped together, photo-bombed each other and posted pictures together.

On Kloss’s birthday, Swift posted a selfie of Kloss and herself on Instagram bearing the caption, “I LOVE YOU KARLIE! You’re such an exquisite person, always trying to make things better for others. Every day I’m inspired by how giving, loving, and thoughtful you are. Happy 24th Birthday!!! @karliekloss”

That afternoon, Kloss tweeted a photo of her computer screen showing a video chat with Swift. She captioned the photo, “When you’re halfway around the world & your best friend still finds a way to celebrate 24 with you.”

But just a few days later there was no better way to celebrate Kloss’s birthday than to hit the Hamptons and party together in-person. A video on Twitter shows some of Swift’s performance.

This was not Swift’s first time in the Hamptons. In February 2015, the superstar shot a Keds commercial at The Surf Lodge in Montauk, and in March 2014, Swift shot an episode of The Barefoot Contessa with Ina Garten in East Hampton. She was also seen dining in East Hampton with director Steven Spielberg in July of 2014.

Nelly brought Taylor up on stage at Karlie Kloss’ birthday party to sing his hit song ‘Dilemma’ together! pic.twitter.com/sumSFEzrQW

— Taylor Swift Updates (@1989TUpdates) August 7, 2016