The proud parents made the announcement via Twitter.
@gwenstefani welcome APOLLO BOWIE FLYNN ROSSDALE 2/28/14 (bowie and Flynn =mothers' maiden names )— GAVIN ROSSDALE (@GavinRossdale) March 1, 2014
Earlier this year, the 44-year-old No Doubt singer revealed she was expecting yet another boy. "I was ready to hand over the crown. but I guess I am still queen of the house. #itsaboy #surroundedbyboys" she said on Instagram.
Stefani and Rossdale have been married for 11 years, and are already parents to sons Kingston, 7, and Zuma, 5.