Actor Brad Pitt seems to have taking serious his role as a father for Angelina Jolie's children. During the past few weeks, Brad was reportedly taking care of Maddox and Zahara, playing and loving them like they were his children.

An onlooker says: "Brad appeared very natural and confident with Angelina's children. He seemed very content and extremely happy.

"He looks like the perfect family man when he is with Zahara and Maddox, and they clearly love him to bits."

Brad flew in from Calgary, Canada, where he is shooting "The Assassination Of Jesse James" By The Coward Robert Ford, to look after Maddox, four, and six-month-old Zahara, while Angelina Jolie films "The Good Shepherd" in New York.