Jack Osbourne has been diagnosed with multiple sclerosis.
The 26-year-old - who has recently become a father - was found to have the incurable autoimmune disease after a frightening spell in which he lost 60% of the vision in his right eye.
He and his family have revealed his condition in an interview with Hello! magazine in which Jack said he had experienced a range of emotions.
– Jack Osbourne
While I was waiting for the final results, I got really, really angry," he said."Then I got really sad for about two days, and after that I realised, being angry and upset is not going to do anything at this point - if anything it's only going to make it worse."'Adapt and overcome' is my new motto."
Thank you all so much for the kind and inspirational words. It means a lot. #adaptandovercome
He has spoken out to raise awareness of the condition and the support of his fiance Lisa Stelly - who gave birth to baby Pearl two months ago - is helping him to keep a positive outlook.
Jack went for tests at the same hospital his daughter Pearl had been born just three weeks earlier. The condition affects the brain and the nervous system.
– Jack Osbourne
"The timing was so bad. I'd just had a baby, work was going great - I kept thinking, 'Why now?"'
Jack Osbourne can be role model for multiple sclerosis sufferers, MS survivor and advocate Nancy Davis told Daybreak this morning.
Black Sabbath star Ozzy and former X Factor judge Sharon have also been stunned and are still struggling to come to terms with their son's condition, which was confirmed by a neurologist last month.
– Sharon Osbourne
I keep thinking, 'what did I do wrong? What did I eat or drink when I was pregnant?' I feel like it's somehow my fault."
– Ozzy Osbourne
If it was me, you'd think: 'Ozzy had a reputation and it caught up with him', but Jack is such a good guy."
Jack - an extreme sports enthusiast - will use a combination of daily drug treatments, holistic therapies and lifestyle changes.