The film could not have been made without the contributions of Reeve’s family, so it’s noteworthy when Reeve’s son Matthew opens up to the camera in the above, exclusive clip to discuss his favorite moment in his dad’s remarkable film career.

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

The late Christopher Reeve's children stepped out together for the premiere of "Super/Man: The Christopher Reeve Story," which explores the legacy of their beloved father. The documentary follows Christopher Reeve's life as he became the iconic "Superman" character and after he was paralyzed in a near-fatal horse-riding accident in 1995.