Kid Rock will soon be adding another title to his name: Grandpa. The singer's 21-year-old son, Bobby Ritchie, Jr., is expecting a child.

US Weekly reports that this will be the first child for Ritchie and his girlfriend, who is four months into her pregnancy. The couple is expecting a baby girl.

Rock has not yet commented on becoming a grandfather, but the singer, 43, raised Ritchie, Jr. almost entirely on his own. The 'Picture' hitmaker won a custody battle against his son's mom, Kelley South Russell, back in 2002. Ritchie, Jr. was born in 1993.

Rock admits he hasn't been a perfect parent, but he takes his job seriously, which will no doubt continue when he becomes Grandpa Rock. The singer spoke to Esquire in 2011 and joked that he and Bob Ritchie -- his real name -- are two different people, one of whom is extremely responsible.

"Make no mistake,” Rock said at the time, “Bob Ritchie’s up early in the morning taking pictures of his son on the first day of his senior year. Kid Rock is passed out in a hotel room somewhere with four scantily clad women."

Congratulations to Bobby Ritchie, Jr., his girlfriend and soon-to-be grandfather, Kid Rock!

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