Today (Aug. 25) is a very special day for Def Leppard and Dio fans everywhere -- Vivian Campbell turns the big 5-0! Happy birthday to the famous guitar player who's kept us metal heads rocking and rolling all night long.

Before Campbell joined Def Leppard in 1992, he played alongside the late, great Ronnie James Dio in Dio between 1983 and 1986. It's been no public secret that there was quite a feud between the two, before the singer's untimely death from metastasized stomach cancer. Campbell himself talked openly about the problems he had with Dio and his wife, Wendy, whom he claimed "excluded him" from important decisions.

Still, even if it was only for a brief time, the two made wonderful music together. Here's a snap of Campbell and Dio in happier times. Our only regret is that there is no dragon and/or snake joining them in the shot.

Campbell announced recently that he has plans to reunite the original Dio band with a new singer so he can reclaim those rocking riffs that helped launch his career. So to you, Mr. Campbell, on your fiftieth birthday, we wish you the very best of luck with both this endeavour and your continued work with Def Leppard.

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