People across the globe came together Monday to mark International Holocaust Remembrance Day. It marked the 80th anniversary of the liberation of Auschwitz, the deadliest concentration camp during World War II.

Holocaust survivors, world leaders and descendants of victims gathered at the former Auschwitz site to pay tribute to the millions who lost their lives during the war. Among them was the family of Nat Ross, a survivor who passed away last year at the age of 101.

Ross's granddaughter, Dana Arschin of Port Washington, has made it her mission to keep his memory alive.