Bill O'Callaghan, 75, hangs a portrait around his neck of his brother Lt. Daniel O'Callaghan, who was killed during the 9/11 attack, as he attends a memorial service for the fallen firefighters at St. Patric's Cathedral as part of the commemoration of the 20th anniversary of the September 11, 2001 attacks in New York City, New York, U.S., September 11, 2021. REUTERS/Go Nakamura NO RESALES. NO ARCHIVES. 