People.com: There's a new crooner in town!

Country star Brad Paisley, 36, and According to Jim actress Kimberly Williams-Paisley, 37, have welcomed a son, her rep tells PEOPLE exclusively.

Born in Nashville, he's the second child for the couple, who are also parents to 2-year-old son William Huckleberry Paisley, who's named for Mark Twain's famed character, Huck Finn.

"We're having so much fun with our little boy Huck, and we are thrilled that he will have a sibling," Williams-Paisley told PEOPLE when she announced her pregnancy last year.

"I never had [a sibling]," said Paisley, who kissed his wife's baby bump at the Country Music Association Awards last November. "I was an only child. I think [Huck] will be a great big brother. He'll learn to share, which is something I never did!"

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