This look back at Sept. 11 details how that day impacted several people, including flight attendant Elise O'Kane, who would have been on United Flight 175 if not for a typing error. Here, she meets the family of the man who took her spot. Also profiled are Shirley Brooks-Jones, whose flight was diverted to Newfoundland; and singer-songwriter Mary Chapin Carpenter, who was in NYC that day, and wrote a song based on an ironworker's experiences.