Facebook founder and CEO Mark Zuckerberg announced Tuesday that he and his wife, Dr. Priscilla Chan, will give 99 percent of their shares away—roughly $45 billion—to honor the birth of their first child, a daughter named Max. "We love you and feel a great responsibility to leave the world a better place for you and all children," Zuckerberg and Chan said in letter to their daughter, posted Tuesday to Facebook. "We wish you a life filled with the same love, hope and joy you give us. We can't wait to see what you bring to this world."