Taylor Swift and Brittany Mahomes have a secret handshake. Here's a timeline of their friendship.

The two first connected after Kelce talked about how he'd hoped to meet Swift when he attended The Eras Tour on a July episode of his podcast, "New Heights."

In her interview for Time magazine's Person of the Year issue in December, Swift confirmed she and Kelce began dating shortly after the episode aired and were already a couple when she attended her first Chiefs game in September.

Swift also brought along friends Blake Lively and Ryan Reynolds.

The Chiefs ended up winning the game 8-19.

In a December interview with CBS Mornings, Patrick Mahomes called Swift "part of the Chiefs kingdom" and said her handshake with Brittany was "better than me and Travis'."

"It's cool that she's embraced Brittany, and they've built a friendship as well," he said. "So for me, it's Travis, man, and he's lucky enough to be with a great girl, and a great woman, and it's been cool to interact with her."

The group dined at BONDST, a sushi restaurant in NoHo. Princess Beatrice was also spotted at the restaurant that night, though she did not arrive as part of Swift's group, Town and Country reported.

Days later, Mahomes introduced Swift to her football friends. On November 7, she posted photos on Instagram of herself and Swift posing with Lyndsay Bell, who is married to Chiefs tight end Blake Bell, and Paige Buechele, who is married to former Chiefs quarterback Shane Buechele.

They gripped each other tightly as they watched the game, which the Chiefs lost 19-27.

Mahomes posted a photo on her Instagram stories from their stadium suite showing a cookie decorated with the words "dads, Brads and Chads," referencing a quip Swift made in her Time Person of the Year interview about how often she is shown on football broadcasts.

"There's a camera, like, a half-mile away, and you don't know where it is, and you have no idea when the camera is putting you in the broadcast, so I don't know if I'm being shown 17 times or once," she said. "I'm just there to support Travis. I have no awareness of if I'm being shown too much and pissing off a few dads, Brads, and Chads."

Swift's hat featured Kelce's number, 87, while Mahomes wore her husband's number, 15.

Mahomes posted a photo with Swift and Bell on her Instagram stories, captioned "Christmas girlies." Swift's brother, Austin, also attended the game in a full Santa costume.