TV highlights: 'Girl Meets World' premieres on Disney

For your Friday night cry, "A Leap of Faith: A Meredith Vieira Special" (NBC at 8 p.m.) introduces us to Paolo Macchiarini, a doctor trying to revolutionize the way diseases are treated with regenerative medicine. Viewers also meet the people Macchiarini is helping as they share their life experiences with the NBC News co-host.