Carrie Underwood's baby a boy

Carrie Underwood is expecting a baby boy.

Country singer Brad Paisley accidentally revealed the 'See You Again' singer will welcome a son into the world with husband Mike Fisher next spring.

Paisley was co-hosting the Country Music Awards (CMAs) with the blonde beauty in Nashville, Tennessee when he made the slip.

During their opening monologue, Brad begged her to reveal the gender of her unborn baby and after some persuading she whispered the answer in his ear.

He then gloated: "I know something you all don't know."

But, according to E! News, he later let the cat out of the bag while talking about Garth Brooks, when he gestured at Carrie's growing baby bump and said: "We should call him Garth."

Though the 31-year-old singer is excited about becoming a mother for the first time, she recently admitted she is nervous about the responsibility.

Discussing her concerns about becoming a parent, she said: "Just being responsible for a tiny human. That's the hardest part."

Carrie also previously admitted she is finding the fact she is pregnant "weird".

She said: "It's still kinda weird, to be honest. Sometimes I'll be with my husband, and it's like, I'm gonna be a mom. You're gonna be a dad. Is this real life? But we're really excited."