Taylor Swift, Brittany Mahomes cheer on Travis Kelce, Patrick Mahomes at Chiefs-Patriots game

"Taylor Swift supports Travis Kelce at Chiefs game with new BFF Brittany Mahomes, and celebrates her birthday early at party."

Taylor Swift is showing her support for Travis Kelce once again. The singer spent her Sunday cheering on the Chiefs with her new BFF Brittany Mahomes. The two sat together in a suite as they watched the Chiefs defeat the New England Patriots at Gillette Stadium in Foxborough, Massachusetts. They were joined by Swift's dad, Scott Swift, as well as singer Alana Haim, fashion consultant Ashley Avignone, and one of Swift's longtime back-up singers, Melanie Nyema, as they rooted for Kelce and the Chiefs.

Swift wore a knit Chiefs beanie embroidered with her boyfriend's jersey number, 87, along with a gray team shirt, a skirt, and her classic red lip. Mahomes wore a black turtleneck and pants, and kept cozy in a fluffy white coat for much of the game. In a playful nod to a comment made by Swift in her Time Person of the Year cover story, Mahomes posted a photo of a cookie on her Instagram Story during the game, decorated to say, "Dads, Brads and Chads."

Swift has said that she goes to games solely "to support Travis" and has "no awareness" of how often she's shown on TV, nor does she care about "pissing off a few dads, Brads and Chads." Since Swift started dating Kelce this summer, she and the wife of Chiefs quarterback Patrick Mahomes have spent many Sundays together cheering for the reigning Super Bowl champs. They've even developed a special handshake and have broadened their friendship beyond football stadiums.

A source told PEOPLE that "everyone had a blast" when Brittany joined Swift's pals in New York two months ago. "They all got along and were just laughing all night over drinks and delicious food," the source said. The "Cruel Summer" singer's appearance at Sunday's Chiefs game comes after she celebrated her birthday in New York City last week, though she was notably without Kelce by her side on the day.

The tight end had mandatory practice on Wednesday, when Swift turned 34, and PEOPLE confirmed that he had to be in Kansas City. The couple had instead celebrated her birthday a few days early at a team party following the Chiefs loss against the Buffalo Bills last week. They were spotted posing with partygoers and exchanging sweet kisses in group photos throughout the evening, and Kelce's barber later shared a photo that Swift took herself as the NFL star got a pre-game haircut.

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