When expecting a new baby, some couples wish and hope for one sex over another, but Carrie Underwood insists she and Mike Fisher already knew their son would be a boy.

However, they didn't want to learn whether the baby was a boy or a girl in a doctor's office. "It’s kind of a sterile place," Underwood tells KTIC Radio. "We got to see all the pictures and everything. It was really cool to see that, but whenever she’d get near ... near those parts ... we would look away.”

Instead, the singer and her hubby broke the news to themselves while on a dinner date. They brought the envelope containing the secret to the restaurant and opened it there, together.

“[It was] just the two of us in a nicer setting, but we both knew," the 'Something in the Water' hitmaker assures. "So, that was just confirming our suspicions. We didn’t really speak of it before, ’cause we were both just like, ‘Whatever. It’s all good.’ But we knew it was a boy."

Luckily, country fans didn't have to wait until the baby's birth to learn the secret, as Brad Paisley "spilled" the sex during the 2014 CMA Awards. Underwood admits she had to wait until the last minute to tell him -- clearly, she knew he couldn't keep his mouth shut.

“Brad’s got loose lips," she explains. "He’s a blabbermouth. So, I was like, ‘I’m not gonna tell you until we’re ready for the rest of the world to know, ’cause I know you’ll tell people.'”

Baby Fisher is expected in the early part of 2015.

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