Kellie Pickler says her friendship with Taylor Swift has grown while they've been on the road together. The "American Idol" alum tells TheBoot.com that Swift is, quote, "like a little sister to me, it's really true because we both keep each other in line." She admits that she feels closer to the singer than she does to her actual half-sister, explaining that she and her half-sister were raised separately and rarely see each other. Pickler, who at two-years-old was abandoned by her own mother, adds that Swift and her mom are starting to feel like family to her. She notes, quote, "Taylor and her mom, they know a lot about me. I call her mom Momma Swift. She's very good to me."

Swift and Pickler have known one another for two years, and this year they've been touring together on Swift's first headlining trek. Their next collaborative stop will be at the Calgary Stampede in Calgary, Alberta, Canada on July 8th. Pickler will be on her own for her next appearance, in Round Rock, Texas on July 4th.