Jack Osbourne on his multiple sclerosis diagnosis: Being angry and upset will only make it worse!

Yahoo! TV

Just weeks after Jack Osbourne celebrated the birth of his first child in April, he returned to the hospital where his fiancée, Lisa Stelly, had delivered their daughter, Pearl Clementine, and received devastating news: He has multiple sclerosis.

"The timing was so bad," the 26-year-old son of Ozzy and Sharon Osbourne told the British magazine Hello! magazine of his recent diagnosis. "I'd just had a baby, work was going great … I kept thinking: 'Why now?'"

Jack -- who appeared on the MTV reality series "The Osbournes" with his famous family when he was a teen -- explained that he went to a doctor after a frightening incident during which he lost vision in his right eye. After testing, Jack learned he has multiple sclerosis, an incurable autoimmune disease that attacks the brain and central nervous system. MS can also cause problems with vision, balance, muscle control, strength, and thinking.

[Related: 'America's Got Talent': Watch a mini-Ozzy Osbourne wow Sharon Osbourne]

"While I was waiting for the final results, I got really, really angry," he told Hello!. "Then I got really sad for about two days, and after that I realized: '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."

His treatment plan includes a combination of daily medication, holistic therapies, and changes to his lifestyle.

[Related: Sharon Osbourne talks about her granddaughter, Pearl]

Jack is being showered with support by his family, who were reeling from the news. "I keep thinking: 'What did I do wrong? ... I feel like it's somehow my fault," Sharon told Hello!. His rocker father, Ozzy, was interviewed for the story, and he said the news hit him hard. "If it was me, you'd think: 'Ozzy had a reputation and it caught up with him', but Jack is such a good guy."

Meanwhile, Jack's sister Kelly addressed his diagnosis on Twitter, writing: "Thank you all so much for the kind and inspirational words. It means a lot. Please support my brother @mrjacko in not only his bravery but honesty! i love you so much jack & I'm so proud of you!"