It doesn't take much more than seeing a teenager behind the wheel of the family car for a parent to realize the child is growing up. Father of three Garth Brooks acknowledges this fact, saying his oldest, Taylor, is already driving and his middle daughter, August Anna, will be doing so this spring. Youngest daughter Allie Colleen, now 13, has a couple of years to go before she takes the wheel, however.

"It's wonderful they are so grown up now, it's like living with three adults in the house," Garth tells The Boot of his daughters, "They are all as tall as Miss Yearwood [his wife Trisha Yearwood]. It's just amazing to see them grow up."

Garth goes on to say that he realizes his family is amazing when he stops to consider everything about them. "When you look around your house and you see your children and you see what you and Trisha and Sandy [Garth's ex-wife and mother to his three daughters] have worked hard to achieve, it's as well of an oiled machine as a divorced family with three teenagers can be. These girls are turning into their own people. They never agree on anything and they have their own attitudes -- now where did that come from? God has a tremendous sense of humor and he'll plant in your children the things about you that will come back to you!"

The singer says his girls reacted positively when they learned of his new five-year gig at Wynn's Encore Theatre in Las Vegas.

"They were happy to hear that I was going to be out of the house some," the superstar jokes. "They were at the point where they said, 'Dad, do your thing, because we've got our things to do.' I never wanted my youngest to feel my hands on her back, pushing her out the door so I could do music. I don't think they feel that way at all; at least if they do they haven't told me."

"I think I've worked diligently on getting to the point where I'm at," Garth continues. "I realize with all my heart and soul that my job [raising three daughters] is nowhere done. Basically they're becoming teenagers and it's just beginning."

Garth began his five-year run at the Encore Theatre earlier this month. His next performances, all sold out, are New Year's Eve weekend, beginning Jan. 1 and running through Jan. 3. He's also scheduled to perform there Jan. 22-24, and Feb. 12-14 and 26-28. Garth's schedule has him performing at the Encore 15 weekends a year through 2014.