Giving fans a special holiday treat, Gwen Stefani joined her husband, Gavin Rossdale, on stage at KROQ's 23rd Annual Almost Acoustic Christmas show at the Gibson Amphitheatre in Universal City, California on Satruday (December 8).
Though Gavin usually performs the song solo until the rest of Bush joins him towards the end, this time his No Doubt wife helped out with the second verse.
The 43-year-old mother-of-two looked cute in a black mesh top and red, plaid pants, while her hunky hubby wore a white sleeveless shirt.
A witness tells PEOPLE, "The place went crazy. They shared a quick kiss after the performance and Gwen exited the stage while Gavin and his band stayed to finish their set."