Hugh Jackman was scared of the dark as a child.

The 'Prisoners' actor has admitted that when he first became a parent to his adopted children, 14-year-old Oscar and eight-year-old Ava, with his wife Deborra-lee Furness he didn't have any idea how to be a father and thinks it's because he was an anxious child who had various fears.

He said: ''I was surprised how little my own parenting instincts kicked in. I was a bit of a pain in the arse at first, insisting he couldn't have a bottle straight before bed because I'd read up on it.

''My own mother finally said, 'Look, you may have read a lot of books, but the kid [Oscar] hasn't, so put them down.' But I was quite a fearful kid myself. Heights, the dark...''

The 45-year-old Hollywood star admits he even incorporated a fear into his 'X-Men' character Wolverine because he didn't want to play someone who isn't capable of feeling scared.

He said: ''I put a fear of flying into Wolverine that wasn't in the script. I thought, 'I can't like somebody who isn't scared of anything.'''