Brad Pitt in Newsweek

Fatherhood, he says, helped accelerate his activism. Not long before Shiloh was born, Pitt adopted Jolie's son, Maddox, whom she originally adopted from Cambodia, and her daughter Zahara, whom she adopted last summer from Ethiopia. "I look at [Zahara] and imagine what her life could have been," he says. "You want to grab as many of these kids in your arms as you can. They need our help, and we should be doing more."