Jack Osbourne has admitted he was not surprised when he found about his dad, Ozzy, had “fallen off the wagon”.

27-year-old Jack Osbourne, who is a recovering addict himself, has spoken out about the recent revelations that Ozzy is drinking and taking prescription drugs again.

Speaking on America's The Dr. Oz Show, hosted by TV medic Mehmet Oz, Osbourne explains, "He's sober now but he did have a relapse. At the end of the day, we're alcoholics. That's what we do. He fell off the wagon, but he does what we're taught to do and he got right back on. It's a tough battle."

Speaking about his own addictions Jack said:"I got sober when I was 17-years-old, so it's one of those things where most people have never had a drink at 17 years old let alone they'd never have to come to terms with having to get sober at 17."

Ozzy’s wife, Sharon, has said she was devastated when she found out that her husband was drinking and taking tablets behind her back.

She said: “My husband has been using alcohol and prescription drugs for the last year-and-a-half...

"Everybody knows he's been struggling with this his entire life. I never knew that he was using prescription drugs; I knew he was drinking, occasionally, but I didn't realise to the extent."

She added: "We're not getting divorced, however, am I happy? No. Am I upset? Yes, I am. I'm devastated right now."