It's still a little hard to believe that AC/DC finished work on its next album without ailing co-founder Malcolm Young. But if a band biographer's inside information is to be believed, fans may need to prepare themselves for Young's permanent absence from the lineup.

Jesse Fink, author of the new book 'The Youngs: The Brothers Who Built AC/DC' (an exclusive excerpt from which can be read right here), was asked about Malcolm's health woes during a recent appearance on the Boston radio station WZLX, and responded, "I’m not expecting to see Malcolm return." According to Fink, the Youngs' nephew Stevie, who filled in for Malcolm during the sessions for their upcoming LP, could well be in for the long haul. "I think the important thing is we all let Mal be and hope he can recover. But I think we should all expect that Stevie Young is in the band now."

Fink declined to go into further detail regarding Malcolm's health during the interview, and he reiterated his respect for the family's privacy when reached for comment by UCR. "As far as I'm concerned, his illness is a private matter," he explained. "However, fans seem to think his illness is just going to quickly go away and he's going to be there on stage when they announce their tour. If what I have heard from numerous sources is true, then I expect Stevie Young will be touring with the band and not Malcolm. That's not a seditious viewpoint. It's realistic."

It's sad news for fans and well-wishers who've been holding out hope that Malcolm would be able to recover enough to rejoin the group, but Fink was able to offer a silver lining in the form of some advance buzz on AC/DC's new music. "I'm hearing on very reliable authority the new album is up there with (2009's) 'Black Ice' or even better," he added. "So Stevie must be a good replacement for Mal."

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