[article id="1608180"]Kellie Pickler[/article] returned to the [article id="1608895"]"American Idol" stage Wednesday night[/article], and this time she didn't have to prove to the judges why she deserved to be there. The season-five alumna was there as a country star in her own right.
The 22-year-old sang her new single "Best Days of Your Life," which was co-written by her [article id="1606856"]soon-to-be tourmate, Taylor Swift[/article], whom Kellie describes as her "little sister."
"We actually wrote my new song that's on country radio right now, 'Best Days of Your Life,' " she told MTV News last week, adding that the two girls met a few years back. "We just kind of blossomed into this wonderful friendship, and she's like a little sister to me."
Not only did the girls write the tune together, but [artist id="2385935"]Pickler[/artist] also managed to get Swift to co-star in the song's video. "We actually just shot the video in Nashville, and it was fun for her to come in," she said. "We wrote the song together, and she sang harmony on the record."
The plan to appear together in the video has actually been brewing for years now. "We wrote this song two years ago, and we said back then that if I record this song and ever make it a single, then we want to do the video together," Pickler said. "Why wouldn't we? We had a good time doing it."
In the time since the girls wrote the song, [artist id="2389485"]Swift[/artist] has definitely become a superstar, and her self-proclaimed older sister has been looking on with pride. "It's amazing to look at how much she's grown as an artist and songwriter and performer," Kellie said. "She's an incredible girl. Very smart, good head on her shoulders."
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