She has co-written twenty of Swift's officially released songs, including "White Horse", "Teardrops on My Guitar", and "You Belong with Me", which won her and Swift a Grammy Award in 2010.
Hon har skrivit flera sånger som spelats in av Taylor Swift, bland andra "White Horse," "Teardrops on My Guitar" och "You Belong with Me," som belönades med Grammy Award 2010.