These days, Carrie Underwood is balancing preparing to be a mom with releasing new music ... by blending the two together, sort of. The singer's first greatest hits album hit Tuesday (Dec. 9), so she's been busy -- but she always finds time to sing to Baby Fisher in the car.

"I kind of just sing along in the car to whatever, but I do feel like there's someone listening to me all the time now," she tells Taste of Country Nights host Sam Alex with a laugh. "I try to sing good."

The blonde starlet did a lot of 'good singing' on her latest release, 'Greatest Hits: Decade #1,' which is comprised of her biggest songs to date as well as a few new ones, including 'Something in the Water.'

As the first single from the double-disc album, the faith-based song topped both the Hot Country Songs  and Hot Christian Songs charts. Mike Fisher's wife insists that she doesn't ever set out knowing she'll hit No. 1, but loves it when it happens.

“It’s not everything,” Underwood says of scoring chart-topping hits. “You just want to make great music and then you hope people will like it. It’s just wonderful when you get positive feedback, but I love it for us and for the whole team and for the fans and for the other writers and stuff like that when we get to have a celebratory party for something reaching that No. 1 spot. It’s fun."

'Greatest Hits' stays true to its name, offering several of the singer's past No. 1s. Understandably for an artist of her stature, Underwood had a tough time narrowing down which songs to include.

“I wanted it to be a true thing," she says of the selection. "I didn’t wanna have to cut anything out and I honestly was like, ‘Everybody’s gonna hate me and they’re probably gonna tell me 10,000 reasons why I can’t put them on there,’ but everybody was so supportive. Then I was like, ‘Well, if we’re gonna have two CDs in one anyway, I might as well shove some more stuff on there. What else can I put on there?'"

Underwood's 'Greatest Hits: Decade #1' is available now and includes 25 of the singer's best tracks.

Sam Alex is the host of Taste of Country Nights radio, a syndicated night show which airs on more than 60 Townsquare Media Group stations nationwide.

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