Thanks to her songs "Unwritten" and "These Words (I Love You, I Love You)," Brit-pop star Natasha Bedingfield [ tickets ] found fame in the United States in 2005. But that wouldn't be the case if she hadn't penned a song for younger brother and fellow artist Daniel Bedingfield.

"I was surprised it was a hit," Bedingfield said during an interview with LiveDaily. "It's because it was a song I wrote just as a birthday present for my younger brother. When 'Unwritten' did that well, it was really, really exciting. But I wasn't thinking about trying to please people with that song."

Well, she did, and the ubiquitous song made its way on to a commercial for a hair-care line. Two years after its release, "Unwritten" lost out to Christina Aguilera's "Ain't No Other Man" for the Best Female Pop Vocal Performance Grammy.

Bedingfield forged ahead with her new album, "Pocketful of Sunshine," which spawned the summery hit "Love Like This," and now she has embarked on her first headlining tour of the United States. (The itinerary is included below.) On the eve of the tour, Bedingfield could barely contain her excitement.

"I'm really excited about this tour coming up," she said. "This is the first time I'm headlining a US tour. There's lots of dates. Today is the dress-rehearsal day. I guess they call that 'production day.' We try out all the lights, and the whole set. It's going to be cool."

While the album "Unwritten" told tales of female empowerment, "Pocketful of Sunshine" is a logical follow-up, covering her experience since then.

"My first album was definitely about independence and individuality and making the most of every moment," Bedingfield said. "Really, I've done a lot of that in my life. I've really experienced a lot and the next album is the next step up from that, with the experiences that happened along the way.

"It's about relationships, the ups and downs, and even just growing up. There's some songs on the new album about when your parents try and tell you how your life should be. You're like, 'Actually I just need your heart right now, not your mind.' It's very soulful music--pop music with meaning, really."

Millions of folks heard her "pop music with meaning" when she appeared on "American Idol" toward the end of season seven. She was able to witness, first hand, the snarkiness of "American Idol" judge Simon Cowell, as well as the backstage room with the final three contestants.

"It was great to perform on 'American Idol,'" she said. "It was really quite exciting to be backstage with all that tension of people wondering if they're going to be in or out that week.

"Simon kept his arms crossed throughout the whole performance. It was like, 'Are you trying to scare me or something Simon?' Every time I saw him, I would say cheeky things. He ended up saying, 'You're quite lippy aren't you?' I said, 'Yep, I am,'" she added with a laugh.

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