More than 1750 quilted flags now hang in Boston's Museum of Fine Arts. They're adorned with images and messages of love and peace.
Campbell says she wanted to do something positive in response to such a terrible act.
"It was very sad and shocking, obviously," Campbell said in an interview with CBC Radio One's Stephen Quinn On the Coast.
"It was weighing heavily on my mind how separated we've become as a society and how we've forgotten to be kind to each other just as human beings."
The North Vancouver artist says the inspiration for the project that spread across the globe came to her in a dream.
"I had one of those weird lucid dreams that I had made some love banners and it made me feel good." said Campbell.
After making a few quilted flags of her own, she contacted her quilting guild to see if they wanted to help. From there, the project spread quickly to guilds and groups throughout North America and eventually attracted pieces from countries across Africa and Europe.
The project became so popular, that the Boston Museum of Fine Arts, with some prodding from a well-known Boston quilter, decided to feature the flags in its gallery.
One of the flags Campbell designed and sewed features the words of Martin Richard, an eight-year-old boy who was killed in the explosions. It simply says "No more hurting people".
"Eight-year-olds should not be worried about being shot at school or being bombed. They should be having fun, so that weighed on me," she said.
"That was just my little thing for him because I really feel for his family."
Three people were killed and 264 were injured on April 15 when two homemade bombs exploded near the finish line of the Boston Marathon.
On the Coast airs Monday to Friday from 3 p.m. to 6 p.m. on CBC Radio One in Vancouver. 88.1 FM / 690 AM.
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