AceShowbiz - Rock matriarch Sharon Osbourne credits her son Jack Osbourne's determination to get clean with inspiring Ozzy Osbourne to kick his addictions to drink and drugs once and for all.

The "Paranoid" hitmaker's lifelong battle with alcohol and illegal substances has been well documented over the years, but it was only when Jack checked into a child psychiatric ward to deal with his personal issues in 2003 that the Black Sabbath frontman became serious about confronting his own problems.

Speaking in candid new documentary "GOD Bless Ozzy Osbourne", which was produced by Jack, Sharon says, "Jack getting sober was... really his big turning point... Jack was dealing with life sober for the first time."

The 62-year-old singer has spent the past few years completely sober after vowing to clean up his act for the sake of his loved ones and his dedication to the cause has stunned even his closest relatives. The Osbournes' eldest daughter, Aimee Osbourne, says, "He's really blown us away... It really seems like he's come through the other side."

Kelly Osbourne reveals she is proud of her dad for sticking to his promise, "I spent 19 years of my life praying he was the father I have today. Not many people can say that." And Sharon has echoed her daughters' sentiments, adding, "He works really hard for his sobriety and he deserves it."

"GOD Bless Ozzy Osbourne" premiered at the Tribeca Film Festival in New York on Sunday, April 24.