Dax Shepard has revealed his daughters knew when he had relapsed.

Dax Shepard and Kristen Bell

Dax Shepard and Kristen Bell

The 46-year-old actor - who explained earlier this year that he relapsed into taking Vicodin again following a motorcycle accident after several years sober - has opened up on how he discussed the issue with his and Kristen Bell's kids Lincoln, eight, and six-year-old Delta.

Appearing on Chelsea Clinton's 'In Fact' podcast, he said: "They knew when I relapsed. We explained, 'Well, daddy was on these pills for his surgery and then daddy was a bad boy and he started getting his own pills.'

"Yeah, we tell them the whole thing... They know that dad goes to an AA meeting every Tuesday and Thursday."

And Dax noted his children have already been very supportive of his struggle.

He added: "One of the cuter moments was — I wanna say my oldest daughter was three — back when my daughters wanted to be with me 24 hours a day.

"She said, 'Where are you going?' I said, 'I'm going to AA.' She said, 'Why do you have to go?'

"I said, 'Because I'm an alcoholic and if I don't go there, then I'll drink and then I'll be a terrible dad.' And she said, 'Can I go?'

"I said, 'Well, no, you got to be an alcoholic.' And she goes, 'I'm gonna be an alcoholic'. I said, 'You might become one. The odds are not in your favour, but you're not there yet.' "

However, the actor admitted returning to his meetings after his relapse as difficult, particularly because he had "build this whole identity" in his head about his sobriety.

He explained: "I had to go to my f****** meeting I've been going to for 16 years... It was terrible.

"Weirdly, it was terrible leading up to it because I had built this whole identity in my head around having 16 years.

"I loved having 16 years. I was holding onto that so much, I was really scared of not having that."