The interview will appear in next Friday's issue of People magazine. Osbourne's mother, Sharon, was also interviewed for the piece.
Jack Osbourne has been diagnosed with multiple sclerosis.
The son of heavy metal legend Ozzy Osbourne told People he got the news just two weeks after he and his fiancee, Lisa Stelly, welcomed a daughter, Pearl Clementine, into the world.
A disease that affects the central nervous system, the effects of MS can be minor or seriously disabling. It can affect muscle control, strength, vision, balance thinking and feeling.
Osbourne was clearly emotional about the timing of the ordeal.
"I was just angry and frustrated and kept thinking, 'Why now?'" the former reality star told People. "I've got a family, and that's what's supposed to be the most important thing."
The interview will appear in next Friday's issue. Osbourne's mother Sharon was also interviewed for the piece.
Suggested Reading: People