Jack says his dad has genuinely impressed him with his resiliency, in spite of how Parkinson's threatens his future as a performer.
"The toughest thing for me about that process was that, with someone like my dad, who has been a part of his craft and actively working for 50 years, is that, when you tell that person, 'Hey, you might not be able to do that anymore,' the worry is that, like when a racehorse can't race anymore, they lose the will to keep going, and that was my worry," Jack told Collider. "He got this really god awful diagnosis and he had a bad injury, as a result of it, and there was genuine fear that he might not be able to perform his craft anymore. That was what I found very upsetting."
Ozzy found it upsetting, too. He's often said that, even after his farewell tour ends, the only way he'll stop performing is when he's dead.
But Ozzy is "doing much better," Jack says. And he's turned his disappointment into determination.
"He's come to terms with where he's at, a little bit more, and he's slowly recovering. I do think he'll make it back out on the road, eventually. It was just a really tough thing to face. He had this whole tour planned, and it was difficult for him. It was difficult for all of us because we just saw how hard he was taking it."
While Jack grew up in a dramatically different environment from working class Birmingham, England, where his dad is from, he says his father passed on his blue collar work ethic.
Jack's latest venture is the Travel Channel series Portals to Hell.
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