Tragedy has struck the Ratt family, with the death of frontman Stephen Peacy's sister. That's led to the cancellation of the group's appearance as part of the upcoming Monsters of Rock cruise.

Ratt had already announced it would be replacing Bobby Blotzer for the show, as he continues recovery from neck surgery in October.

"We are deeply saddened to report that Stephen’s sister has passed away," Ratt said, in an official statement. "Due to this sudden and unexpected news, Ratt will not be performing on Monsters Of Rock. We would like to thank our loyal fans for their support and understanding. We ask that you kindly respect Stephen’s privacy during this difficult time.”

Pearcy has previously reported that Ratt was on track to release its 10th studio effort later in 2014, and their first since 2010's Top 40 Billboard-charting 'Infestation.' Pearcy said that long-time guitarist “Warren DeMartini and I are spearheading the next record to be what it should be: a more 'Out Of The Cellar' thing. Just real hard-core, basically.”

Blotzer was scheduled to be replaced on the cruise by Jimmy DeGrasso, the former Megadeth drummer who earlier filled in on a trio of January concerts with Ratt.