Hayley Williamsis decoding how she andTaylor Swiftmet.

(The latter ended up taking home the award.)

Williams recalled, “We were at some Grammy party it was actuallyTimbaland’s Grammy party.

Taylor Swift and Hayley Williams

Taylor Swift and Hayley Williams.Rick Diamond/Getty Images

“I love Taylor’s mom!”

To which Williams replied, “Andrea, the legend that she is.

She connected us.”

Fallon then presented a photo of the pals that featured Swift smiling and Williams excitedly giving a thumbs-up.

“I don’t know why!”

“That’s your thing!”

Williams confirmed, “It is our thing.

It’s just to show how cool we are.”

“They’re so cool and generous for agreeing to support my version.”

Listen to Williams recount the origins of her friendship with Swift in the clip above.