David Arquette has been sober since Dec. 29, and he's ready to share all the details about his alcohol and drug-filled past since cleaning up. During an appearance on 'The Oprah Winfrey Show' airing Thursday, the actor reveals all to the talk show host.

"When I had my first drink of beer, I must have been 4 years old," he told Winfrey [via UsMagazine.com]. "I was down in the basement with my dad, and beer was there, and I just grabbed it and drank it. And I remember that. It's one of my earliest memories."

"I seriously started drinking probably when I was about 12," the 'Scream 4' actor continued. "I stole pot from my father when I was 8 years old."

The 39-year-old revealed it was his wife, Courteney Cox, and sister, Patricia Arquette, who got him to check into rehab on Jan. 2.