A spokeswoman for the singer says the baby was born Friday morning at a Nashville-area hospital. No word yet on his name.
The Paisleys' first child, William Huckleberry, whom they call "Huck," was born in February 2007.
Earlier this month, Paisley won best male vocalist at the Academy of Country Music Awards. He is also the reigning Country Music Association male vocalist of the year.
Williams-Paisley starred on the ABC sitcom "According to Jim" and has appeared in several feature films, including "Father of the Bride."
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