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Jack Osbourne, 26, revealed that he was diagnosed with multiple sclerosis (MS), "an incurable autoimmune disease that attacks the brain and central nervous system." Saddened by the news, his mother Sharon Osbourne couldn't help blaming herself.

"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," she told Hello!. Jack's father Ozzy Osbourne was equally upset. The Black Sabbath rocker said, "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's sister Kelly Osbourne, meanwhile, showed her love for her brother on Twitter. "Please support my brother @mrjacko in not only his bravery but honesty! i love you so much jack & I'm so proud of you!" so the 27-year-old "Fashion Police" judge tweeted.

Jack found out his illness three weeks after welcoming his first daughter Pearl. After losing most of the vision in his right eye, he visited hospital to get himself checked out. It's the same hospital his fiancee, Lisa Stelly, gave birth to their baby girl. "The timing was so bad," he said. "I'd just had a baby, work was going great... I kept thinking: 'Why now?'."

Like his family, Jack was also shocked but he kept a positive outlook. "While I was waiting for the final results, I got really, really angry," he recalled. "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."

He got full support from Lisa as well. "Jack will have to change his life for the better - get healthier, not get stressed - so I feel like this could almost be a blessing in disguise," she said. On Sunday, June 17, she wrote on Twitter, "Happy fathers day to the best daddy in town @MrJackO . We love you tons!"

In a separate interview with PEOPLE, the first-time father said his family's support helped give him the strength to go through the emotional ordeal. "I've got a family and that's what's supposed to be the most important thing," he gushed.

Jack opened up about his disease in an effort to raise awareness of MS. Multiple sclerosis could lead to blindness, slurred speech, muscle weakness and a loss of co-ordination.