Cpl. Nathan Cirillo, 24, was shot fatally from behind by a lone gunman, who then raced into the House of Commons before he, too, was gunned down.
"It was cowardly, it was evil, and most of all, it was tragic," Cirillo's sister Nicole told the assembled crowd.
"When Nathan passed away, our family's snowglobe was shaken and turned upside down, and now everything is falling in a new place. It is unrecognizable. There is sorrow and pain. All we want to do is go back to the world that we once knew."
At the same time, Cirillo said, the tragedy had brought forward an outpouring of comfort and support for the family from all over the world.
Cirillo, a member of the Argyll and Sutherland Highlanders regiment, left a young son, Marcus Cirillo, who goofed around before the ceremony, as well as his mother, step-father and siblings who were in attendance.
The evening ceremony, in near darkness, included a marching on of the colours, a "monument of light," and words from the regiment's padre, Robert Fead.
"We gather to remember, ironically, because he lost his life at the very place where Canadians, particularly those of use who serve in the military, also gather to remember," Fead said.
"May his life and death inspire all of us to work for greater peace in our nation and in our world."
Cirillo was also being remembered for the love that he had for his family, for rescue dogs, his smile and his friendliness, Fead said.
The young corporal and his partner, Cpl. Branden Stevenson, were on ceremonial sentry duty at the war memorial when Michael Zehaf-Bibeau, 32, shot him in the back before storming into the Centre Block on Parliament Hill.
Days after the shooting, politicians, members of the military and friends and family packed a Hamilton church while thousands stood quietly in the streets and watched a the procession of an estimated 4,500 members of the armed forces and first responders marched through the city's downtown.
Coming just 48 hours after Warrant Officer Patrice Vincent, 53, was murdered in a hit-and-run by an Islamic-extremist in Saint-Jean-sur-Richelieu, Que., the assault on Canada's Parliament sent shock waves through the country and prompted an outpouring of grief.
Lesya Dyk, whose son is in the military, said she remembers the shock after the killings.
"We felt such a sense of panic," Dyk said after the Cirillo service on Wednesday. "The military supports their own."
Following the ceremony, attended by some people with candles and others with the Maple Leaf, members of Cirillo's regiment marched back to their local armoury for a final, private dispatch.
On Thursday morning at the War Memorial, Gov. Gen. David Johnston, outgoing Prime Minister Stephen Harper and prime minister-designate Justin Trudeau will be part of a commemoration, along with members of Cirillo and Vincent's families, soldiers from Cirillo's reserve regiment, first responders and police.
There will also be a 21-gun salute and a flypast by four CF-18 fighter jets, similar to Remembrance Day ceremonies.
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