Editor's Note: In an American Morning original series, “Big Stars, Big Giving,” Alina Cho looks at celebrity philanthropy and how these big stars can make a big impact. Through one-on-one interviews with Elton John, Ben Stiller, Madonna, Martha Stewart and Richard Branson, she shares what causes have become their passion, and how you can get … Continue reading Big Stars, Big Giving: Ben Stiller is 'StillerStrong'