Nikki Sixx regrets not reconciling with his mother before she died.
The Motley Crue rocker was reminded of his turbulent relationship with his mum, Deana Richards - who passed away in 2013 - after watching a key part of his own history in the band's upcoming Netflix biopic, 'The Dirt'.
Nikki explained that it was the most "painful part" of the film, which will be released later this month, because he "regrets" the decision to not "reconcile" with her every day.
Speaking to Forbes, Nikki said: "The most painful part of the film is my relationship with my mother and how I could never mend that.
"There is a scene where she is calling me and I can't pick up the phone. I'm addicted to drugs but have huge animosity because she abandoned me.
"Later I went to rehab and I got sober but she passed away and we never reconciled. I regret that. I continue every day trying to be a better man but we could not close that gap."
The 60-year-old musician - whose band also consists of drummer Tommy Lee, lead singer Vince Neil and guitarist Mick Mars - also insisted that the much-anticipated Netflix film is incredibly "important" to the rockers and is the reason they wanted to have a team who understood their "culture" and the many obstacles they've faced in their long music career.
He added: "Tommy and I weren't sure at first because this was not a comedy and the movie was very important to us.
"Then Jeff [Tremaine, director] came in and gave us a pitch and it blew my mind. He is a fan of the band and he understood the culture.
"This really is a family, my first family. We climbed the hill together and then we imploded and then we came back together and went on for another 20 years. Yes, there is rock and excess, but it could be about a football team. That's the potency of the movie for me."