How Carrie Underwood Learned She's Having a Boy!

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Carrie Underwood announced that her firstborn will be a boy while co-hosting the CMA Awards, but when her baby's gender was first revealed, it was done privately. However, Underwood and her husband, Mike Fisher, didn't want to find out the exciting news in a doctor's office during her sonogram. "It's kind of a sterile place," the country singer tellsABC News Radio. "We got to see all the pictures and everything. It was really cool to see that, but whenever she'd get near those parts, we would look away."

Instead, the couple asked the doctor to write down their baby's gender and put it in an envelope so they could look at it later. They opened the envelope at a restaurant. "[It was] just the two of us in a nicer setting, but we both knew," she recalls. "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."

Co-host Brad Paisley was the one who publicly announced that Underwood is expecting a son. "Brad's got loose lips. He's a blabber mouth!" the American Idol champ, 31, says with a laugh. "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.'"

NEWS: Find out why Carrie Underwood was crying while pregnant

The "Something in the Water" singer announced her pregnancy in September.

Since then, Underwood has said she looks forward to "being responsible for a tiny human" after she gives birth in the spring of 2015. Still, the mom-to-be is already feeling a little frazzled. "We went to Babies'R'Us and we were walking around and I was, like, 'This is just so overwhelming!'" the "Before He Cheats" singer admitted. "I just don't want to get the wrong things, you know? I don't know what most of it does. There are, like, 5,000 things to choose from, and I'm like, 'Do we need that?! I don't know!'"