CHICAGO (CBS) — The suburban carpenter who’s spent more than two decades remembering victims of violence is hanging up his tools and retiring.

Greg Zanis made his first memorial cross after the murder of his own father-in-law. Since then, he’s traveled to dozens of mass shootings to make crosses for the victims.

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From Columbine to Sandy Hook, Las Vegas and Parkland, Zanis has made more than 27,000 crosses.

In a Facebook post, his daughter said his mission has been tough on his own family, but they are proud of him for following his heart.

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