The band's lead singer/guitarist Paul Stanley and his wife Erin, an attorney, welcomed daughter Emily Grace Stanley on Tuesday in Los Angeles, he tells PEOPLE.
Emily, who weighed in at 7 lbs., 10 oz., joins elder siblings Sarah Brianna, 2½, Colin Michael, 4½, and Evan Shane, 17, Stanley's son from a previous relationship.
"Erin and I are once again blessed with the addition of Emily Grace to our family," the rocker, 59, says. "I'm not sure she can sing but her first screams let me know she's definitely Daddy's girl."
Stanley – who's also a successful painter – just completed a series of sold-out KISS dates and is currently producing the band's next album.
As for having kids later in life, Stanley says his age doesn't slow him down.
"I may be 59," he told PEOPLE in February, "but the only rocking chair this rocker is getting ready for is the one for my new baby."
Courtesy Paul Stanley
Reporting by MARISA LAUDADIO