By Lindsay Kimble
Updated December 14, 2015 at 08:40 PM EST
Credit: Jeff Kravitz/BMA2015/FilmMagic

Everyone got into the Swiftmas spirit on Sunday – especially Calvin Harris.

Taylor Swift’s boyfriend was by her side at a Christmas party in Los Angeles on the day of her 26th birthday.

The pair, who have been dating since earlier this year, have been spotted together sporadically since the summer’s end, and were last seen out together publicly in November.

In photos and videos from Sunday’s party, Swift and Harris enjoyed the lavish holiday celebrations together.

A clip of the fête taken by Jamie Iovine (Apple executive Jimmy Iovine’s son) shows an indoor winter-themed dining area, a pen with live penguins and a snow-covered hill meant for sleighing.

Jamie also shared a photo with Harris and Swift, with the caption, “I was just adopted by @calvinharris and @taylorswift mom and dad are gonna show me the good life now.”

According to Iovine’s son, the celebration was the Iovine Christmas party – which happened to fall on the birthday of Swift and Iovine’s daughter, Jessica.

In video captured from DJ Snake’s Snapchat account, the trio posed for a photo with the party’s Santa and Mrs. Claus. Swift leaned onto Harris while they took the image.

Harris spoke about the photo opp in a second clip from the rapper’s Snapchat.

“They didn’t want us to get a picture but we did,” he said while Swift beamed.

Swift’s 1989 concert tour film was recorded during her performance in Sydney on Nov. 28 and will be released on Dec. 20 on Apple Music. On Monday, Swift will share more about the documentary on Apple Music’s Beats 1 radio.