Kellie Pickler's self-titled second album, released in 2008, contains "Best Days of Your Life," a song she co-wrote with none other than country-turned-pop superstar Taylor Swift, who also provides background vocals on the tune and appears in its music video.

Pickler released "Best Days of Your Life" in December of 2008, as the record's second single. It peaked just inside the Top 10 on the Billboard Hot Country Songs chart (No. 9) and earned a Top 50 spot on the Hot 100 (No. 46); the song has also been certified platinum. Below, Pickler tells The Boot about how the song came to be.

Taylor Swift and I actually wrote this song together while we were on tour with Brad Paisley. I had went through a really bad breakup a while back, so we wrote the song about the relationship that went sour.

It's so funny, because Taylor always says that she has the "Picture [to Burn]" song, and Carrie Underwood has "Before He Cheats" ... and now "Best Days of Your Life" -- that's my kiss-off song! [My ex] has heard it, and so has the person he's with now, so I guess it's bittersweet.

This story was originally written by Deborah Evans-Price, and revised by Angela Stefano.

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