And America's Got Talent judge Sharon Osbourne also revealed that he wants to help other people living with the condition.
"Osbournes survive everything. We really do. Jack is doing really, really well," The Sun newspaper quoted Sharon as saying.
"He is really a positive guy, a good guy. His whole life is that he gives back. It makes him feel good and that is just the way he runs his life.
"I have to thank you, everyone, for all their good wishes. It's been amazing for Jack, because I really believe that vibes of prayer definitely help."
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