Jack Osbourne, 26, son of rock legend Ozzy Osbourne, has been diagnosed with multiple sclerosis, the former reality television star revealed to People magazine.

"I was just angry and frustrated and kept thinking, 'Why now?'" a distressed Osbourne told the celebrity magazine in an article posted on its website late Sunday.

"I've got a family and that's what's supposed to be the most important thing," said Osbourne who recently had a daughter, Pearl Clementine, with his fiancee Lisa Stelly.

MS, an autoimmune disease for which there is no known cure, attacks the central nervous system. Symptoms can include loss of muscle control, difficulties with vision and balance, and in severe cases, paralysis.

One of the most high-profile sufferers of the disease in the United States is Ann Romney, wife of likely Republican presidential nominee Mitt Romney, who was diagnosed with MS in 1998.

Romney has said that over the years she has faced a wide range of symptoms of the disease including at times loss of function on her right side and spasms in her lower back.

The article did not say what symptoms if any Osbourne has shown.

He gained fame on the 2002-2005 hit MTV reality series "The Osbournes," which followed the lives of his father heavy-metal singer Ozzy, his mother Sharon Osbourne, as well as his sister Kelly, with whom Jack Osbourne frequently was shown on the program quarrelling.

Since the show ended, news report said Osbourne has worked as a music talent scout for Epic Records and produced a documentary about is father entitled "God Bless Ozzy Osbourne."

[Jack Osbourne pictured on arrival for the 19th Annual Race to Erase MS themed "Glam Rock to Erase MS" in Los Angeles on May 18. AFP Photo/Frederic J. Brown]