Tim McGraw is climbing the charts with "Top of the World," the debut single from his upcoming album, Damn Country Music, but it's another song on the record that McGraw is the most excited about. "Here Tonight," the disc's lead track, features the vocal talents of McGraw's oldest daughter, Gracie, and while talking an 18-year-old into singing with her famous father might seem like an easy task, McGraw says that it was actually one of the more frightening experiences of his entire life.

"It was scary. I was scared to ask her -- I was," McGraw reveals to The Boot. "I didn’t plan on it. I was just making the record; I certainly didn’t plan on having her sing on it or anything.

"I was doing this song, and as I was doing the vocal on it, I was thinking, ‘Man, I bet Gracie’s vocal would sound really cool on this,’" the country star continues. "I just knew the way she sang, because she’s my daughter, and I know how she sings. She has such an energy ...

"Every time I’d go home at night after being in the studio, I’d just hear her voice on this record," McGraw adds; however, "I’m decidedly uncool to her; I’m Dad. I didn’t think that she would think it would be very cool to sing with Dad, especially with her group of friends and her group of musicians."

So, he he worked up the courage to ask her in small doses.

"I asked Faith [Hill] about it. She said, ‘It’s your funeral. You ask her,'" McGraw recalls with a laugh. "So I sent her the song first, to see if she would like it. I didn’t ask her anything about singing it; I just said, ‘Hey, check this song out and see if you like it.’ I didn’t want to play it in front of her.

"But she said she liked it, so it took me a few minutes, and I got the courage up to ask her. It was easy: She said, ‘Yeah, I’ll do it.’ So I said, ‘Well, learn it,'" he continues. "Two or three days later, we were in the studio. She knew it. She had it down."

McGraw says that his eldest might follow in her parents' musical footsteps -- but hopefully not until after she gets an education.

"She’s in college right now, studying music," he says. "That’s her major. She plays in a band. She’s good. She writes, sings. I hope she gets her degree first."

"Here Tonight" is currently available for download on iTunes. Damn Country Music, which is set for release on Nov. 6, is available for pre-order through McGraw's website.

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