Gwen Stefani and Gavin Rossdale have named their third son Apollo.

The 48-year-old Bush frontman confirmed they welcomed a baby boy into the world in Los Angeles on Friday, and they decided to include both of their mother's maiden names in the tot's unusual moniker.

"Welcome Apollo Bowie Flynn Rossdale 2/28/14. Bowie and Flynn = [our] mothers' maiden names," he wrote on Saturday.

The couple also have sons, Zuma, five, and Kingston, seven, together, while Gavin has daughter Daisy Lowe, 25, with ex-girlfriend Pearl Lowe.

The No Doubt beauty, 44, revealed in January that she was expecting another son.