According to People, Zuma Nesta Rock Rossdale was born on Thursday (Aug. 22) afternoon in Los Angeles.
"Kingston, Gwen and Gavin Rossdale welcomed the newest member of their family," Rossdale and Stefani say in a statement to the magazine. "Mother, baby and family are all happy and healthy."
Zuma weighted in at a solid 8.5 pounds.
The couple's first son, Kingston, turned two in May.
Stefani, 38, met Bush frontman Rossdale, 40, at a 1996 concert she was playing with No Doubt. They were married in London in September 2002. They became the parents of Kingston Rossdale, who turns 2 on May 26. Stefani is also the stepmother to Daisy, a 16-year-old daughter whom Rossdale recently discovered he fathered in an earlier relationship.
In addition to her recording career, Stefani was seen on the big screen in Martin Scorsese's "The Aviator."
Like Stefani, Rossdale has done his share of acting, popping up in films including "The Game of Their Lives" and "Constantine."