Kid Rock, 43, to Be a Grandpa Son Bobby Ritchie Jr., 21, reportedly expecting By Evann Gastaldo, Newser Staff Posted Aug 18, 2014 10:36 AM CDT 16 comments Comments This Dec. 30, 2012 file photo shows Kid Rock performing at the Seminole Hard Rock Hotel & Casinos' Hard Rock Live! in Hollywood, Fla. (Photo by Jeff Daly/Invision/AP, file) (Newser) – Kid Rock is going to be a grandpa at the ripe old age of 43. The rocker's 21-year-old son, Bobby Ritchie Jr., is expecting a baby girl with his girlfriend, sources tell Us, adding that the couple is four months along. Ritchie is Kid Rock's son with the rocker's ex-girlfriend Kelley South Russell; Rock raised the boy mostly on his own. For more extremely young celebrity grandparents, click here and here.