"She lived this belief working in a shelter for the homeless until she moved to Europe to be with her fiancé. She would have had no understanding of the callous cruelty that caused her death.
"Please honour her by making your community a better place. Volunteer your time and labour or donate to a homeless shelter. Tell them Chrissy sent you."
Ms Archibald is the first person killed in the attack to be identified.
Canadian Prime Minister Justin Trudeau said he was "heartbroken" that a Canadian was among those killed.
London Bridge Terror Attack
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In a statement on Sunday, Mr Trudeau said: "Canada strongly condemns the senseless attack that took place last night in London, United Kingdom, which killed and injured many innocent people.
"I am heartbroken that a Canadian is among those killed."
Seven people were killed and dozens 48 injured on Saturday night after a van drove into pedestrians on London Bridge before three men got out and began stabbing passersby.
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