MCEnroe, O'Neal's eldest child with her ex-husband, tennis legend John MCEnroe, was arrested by police in New York City last summer (Jul14) and slapped with a charge of felony possession with intent to sell.

The writer previously revealed the drug bust occurred hours after he landed his first publishing deal for Our Town, and he feared the book offer would be retracted after his arrest hit headlines.

MCEnroe recalls, "The scariest moment of my life was feeling like, when I was in jail, for the 20 hours I was in jail, that they (publishers) were gonna pull the deal and that I'd really ruined (my life)... My dreams had come true and I had really gotten in my own way."

The charge was subsequently dropped as MCEnroe agreed to go to rehab, and he credits his maternal grandmother with providing him with the opportunity to turn his life around by exploring the late actress' life on paper.

He has since had Moore's likeness tattooed onto his shoulder so he will never forget the influence she's had on his life.

He explains, "For me, I think she's the most beautiful woman I've ever seen. I think that she's my guardian angel. I think that when I got arrested and was able to start living my life healthier and better and finish the book for her, it felt like I could fulfil the potential that maybe she was never able to."

Moore struggled with drug and alcohol abuse for years following the breakdown of her marriage to Tatum's dad, actor Ryan O'Neal, in 1967. She died from lung cancer in 1997.

MCEnroe's mother, Tatum, also famously struggled with substance abuse.