Daniel Day-Lewis has said that it has been a long transformation for him, from a 'savage' youngster to a devoted dad.
The 50-year-old, who has received a Best Actor nomination in the Oscars for his portrayal of US oilman Daniel Plainview in 'There Will Be Blood', has credited his three kids for bringing out the change in him.
'I was a savage for so many years of my life. There was some seed of determination in me that I was not conscious of,' The Sun quoted him, as saying.
'I was mostly consciously getting into trouble and drunk. '
'And I saw the efforts that others had to make to get me out of it. At a certain age it just became apparent to me that this was probably the work that I would have to do,' he added.
Talking about parenthood, he said: 'It utterly changed my life. I don't think there's a parent on this earth who would give you a different answer.'
'I experienced this vast unknown in the period leading up to me becoming a father. Then, the unknown reveals itself. This is in spite of your preconceived notions.
'Nature also kicks in, and you begin this journey that dwells in your heart. When it comes to parenthood everyone thinks they will be terrible at it.
'We don't think we have it in us. Then you find out that you do, which truly is a miracle in life,' Day-Lewis said.
He added: 'I don't know if I can describe my feelings about being a father in real life.'