Yad Vashem, Israel's official memorial to the victims of the Holocaust, has a name for those who risked their own lives to save others: The Righteous Among the Nations. One American who received that distinction was Varian Fry, who helped organize artist Marc Chagall's escape from France, for both him and his paintings. Ahead of Holocaust Remembrance Day, Lee Cowan talks with the descendants of Chagall and Fry, Debórah Dwork, author of "Saints and Liars: The Story of Americans Who Saved Refugees