Charlie Sheen made awful homemade movies with the Penn brothers

Charlie said in conversation with David Duchovny, 65, at the 92nd Street Y in New York on 8 September to promote his memoir The Book of Sheen, the Penn brothers had a huge influence on his early years, adding: "We just found it as a way to just kind of emulate, mimic, copy what our parents were doing. The two houses that it kind of bounced between - Casa Penn and our place - is really where that all happened."

The son of actors Martin Sheen and Janet Sheen, Charlie remembered how his and the Penn families contributed to their makeshift productions.

He said: "We never really had the resources to do substantial productions. We were reliant on whatever dad would kick in or what the Penn parents, (actress) Eileen and (director) Leo, what they would kick in... basically our prop department was blank guns, blanks and blood."

While the work was rough around the edges, Charlie said it cemented a bond with Sean, now 65, that has endured throughout their lives.

He explained part of his motivation in writing his new autobiography was to show how much Sean and Chris, who died in 2006 and 40 from heart disease, had meant to him - and that he wanted Sean to see that in print.

Charlie added: "A lot of that (book) was written out of love for Sean. I wanted Sean to really read how much his brother meant to me.

"And I was tempted to go to Sean and read him stuff as I was creating it.

"And I was like, 'No, man, that's probably not how Chris would've handled it. He would've walked in and just (said), 'Here it is'."

The Book of Sheen also recounts Charlie's later Hollywood career, including his roles in Ferris Bueller's Day Off, Two and a Half Men and Spin City, as well as his struggles with addiction.

But at its heart, he said it acknowledges the friendships and family ties that shaped him.

Charlie added: "Writing the book was the most challenging job I've ever had, and hands down the most rewarding one."