Christopher Reeve's children Alexandra, Matthew and Will were a united front at the New York premiere of the documentary honoring their late father. See all the red carpet photos

Reeve's three children, Alexandra Reeve, Matthew Reeve, and Will Reeve, an ABC News correspondent, told "Good Morning America" on Wednesday at the premiere that the film is a tribute to their father's legacy and the lasting impact he had on who they are today.

Very few actors embodied the role of a superhero quite like Christopher Reeve. For generations of movie-loving audience members, Reeve was – and is – Superman. He first stepped into the iconic DC role in 1978’s aptly titled Superman,