The actor - who is married to Katie Holmes - describes the story contained in his scripts to Suri and then listens to her questions because he thinks it makes him a better actor.

He said: "I`ll put Suri on a swing and tell her stories when I`m working on a script.

"I`ll start with the beginning of the movie and take her through the story beat by beat. Of course, I make it age-appropriate. She`s four years old. But she asks all the right questions, `Why does that happen?` `Those are the bad guys?` `You`re the good guy, right?`

"It comes down to the same thing as when I was a kid. Can I create a character that will make her happy, that will make her laugh? And you know what? She makes me get better and better, because she`s always asking me to do it again."

Tom - who also has adopted children Connor,15, and 17-year-old Isabella with ex-wife Nicole Kidman - constantly tries to be the best parent he can because of a promise he made his eldest child when she was just a baby.

He added in an interview with America`s Esquire magazine: "I`ll never forget the moment I became a dad. But it`s hard to describe - that level of responsibility, the desire to give such joy. The clarity: nothing is more important than this.

"I remember that first night, just staring at Bella. I was checking her every second, just looking at her, feeling that immediate bond. I was probably looking at her so much that I was keeping her up.

"I made a promise to her - all I can do is the best I can. But I`m not going to say I`m gonna do something and then not do it."
sections: Celebrities