The couple that plays together, stays together! A rock music rarity took place during Bush's set at the 23rd annual KROQ Almost Acoustic Christmas at the Gibson Ampitheatre in Los Angeles on Dec. 8. Bush frontman Gavin Rossdale was joined onstage by his wife Gwen Stefani, a successful artist in her own right as the singer of No Doubt and as a solo act who has churned out hit after hit.

As he usually does, Rossdale started playing 'Glycerine' by himself for the first minute or so, until Stefani surprised the crowd when she took the stage to lend her distinct vocals to Bush's mid-'90s smash hit. It was the first time that the musical couple has performed together in more than a decade, according to band management.

Christmas is always the most magical time of the year, and some real rock 'n' roll magic took place on the stage of this yearly event.

While Stefani has primarily been delivering pop music these days, she looked right at home offering a vocal assist on a rock song. She was dressed in her trademark stage clothes -- plaid pants, a sheer top and heels, with her hair pulled back. She even rocked out a bit onstage as the pace of the song picked up when the rest of Bush joined in for the climax of the song.

The pair sealed the performance with a kiss on the lips! How romantic, since they made beautiful music together - literally. We would not be surprised if the couple's young sons Kingston and Zuma end up as musicians, with this kind of DNA in their veins.

Watch Bush Perform 'Glycerine' With Gwen Stefani

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