The 18-year-old shocked the world by checking into rehab earlier this year (03), after admitting to being hooked on drugs and alcohol.
And Jack says Ozzy - who has a long history of substance and alcohol abuse himself - is determined to remain sober this time as well, after he went into rehabilitation just before his son.
He says, "We made a deal. He wears this charm on his necklace which he's had forever, but if he relapses he has to hand it over to me.
"Dad's about eight days in front of me. OK, I know he's said that he'd stay clean in the past and still ended up using, but he's doing really well this time.
"I reckon it's the first time he's been really serious about it. In some ways, the fact that I had to go to rehab woke him up."23/11/2003 13:51