Jack Osbourne has been diagnosed with multiple sclerosis.

The son of heavy metal legend Ozzy Osbourne told People Magazine he got the news just two weeks after he and his fiancee, Lisa Stelly, gave birth to their daughter Pearl Clementine. Osbourne was clearly emotional about the timing of the ordeal.

"I was just angry and frustrated and kept thinking, 'Why now?'" the 26-year-old Jack Osbourne told People. "I've got a family, and that's what's supposed to be the most important thing."

What is multiple sclerosis?

According to mult-sclerosis.org, MS is an inflammatory disease of the central nervous system - that's the brain and spinal cord. Predominantly, it is a disease of the "white matter" tissue. The white matter is made up of nerve fibers which are responsible for transmitting communication signals both internally within the CNS and between the CNS and the nerves supplying rest of the body.

No two people get MS in exactly the same way and the expression of each individual's disease is as unique as their fingerprints. However, the different courses of the disease, both within an individual and within the whole population, principally differ in their timing, location and severity. In general, people with MS can experience partial or complete loss of any function that is controlled by, or passes through, the brain or spinal cord.

Other celebrities who have had multiple sclerosis

Other celebrities who have suffered from Multiple Sclerosis include:

Richard Pryor - Comedian

Clive Burr - Drummer for the British heavy metal band Iron Maiden

Alan Osmond - Member of the Osmond Brothers singing group

David "Squiggy" Lander - Actor who became famous during his stint on the comedy "Laverne and Shirley"

Annette Funicello - Singer and actress and Walt Disney's most popular Musketeer

Montel Williams - Celebrity and former television talk show host