Jack Osbourne credits his wife Lisa Osbourne for his positive outlook on life.

The 27-year-old star, who has daughter Pearl, two, with the lifestyle blogger, says she has been his rock since he was diagnosed with multiple sclerosis in 2012.

He said: ''I tell her if I was single, it would have been a much harder process to go though.''

Jack, who has just launched his new web series, 'You Don't Know Jack About MS,' found out he had the autoimmune disease, which affects the brain and spinal cord, just two weeks after Pearl was born, and he admitted having a newborn was a great distraction so soon after being diagnosed.

He added to Us Weekly magazine: ''I had to kind of put on hold any genuine fears I had because, at four in the morning, I had to go change a diaper. Being a dad was where my focus was.''

The former reality TV star, whose parents are rocker Ozzy Osbourne and chat show host Sharon Osbourne, is smitten with his daughter, who he says has inherited her grandfather's flair for music.

He said: '''Frozen' sucks her in, and thanks to her I now know all the songs like the back of my hand. I could do 'Frozen on Ice' at home!''