Carol Todd said a stone reading "A beautiful soul is never forgotten" was placed in front of her Port Coquitlam home after the death of 15-year-old Amanda, in 2012.
Todd said she and a friend who was visiting noticed the plaque was missing.
"It got me a little sad and a little upset, so then I posted it on Facebook ... that I was shocked how someone could remove it from my garden and from there it went viral."
She said the stone, while inexpensive, was like a piece of her daughter and she's sad that it's no longer there for her to look at.
Todd said she believes that the person who took the plaque may have been aware of its sentimental value because her address is still listed in the phone directory and there has been some anger directed toward her in the past.
"So I wasn't quite prepared for some of the negative (response), that it would actually come across in real life," she said. "I've gotten some backlash and horrible stuff through social media but in real life it was kind of surprising."
The high-profile case of Amanda's alleged exploitation garnered international attention when a YouTube video surfaced after her death. It showed the teen holding up handwritten signs detailing how she'd been blackmailed by an online predator after exposing her breasts on a web cam.
The video has been viewed millions of times.
Aydin Coban was arrested in the Netherlands last year and is facing charges in Canada of extortion, criminal harassment, Internet luring and two counts related to child pornography.
Coban denied earlier this year that he was "the so-called tormentor" of Todd, yet said he has been branded by the worldwide media as the monster behind the case.
In a four-page letter released by his lawyer in January, Coban said he wanted to mark his first year in prison by addressing the many blatant "lies" that were swirling about the case.
Dutch police said when Coban was arrested in April last year that they had identified between 30 and 40 potential victims in the Netherlands and others in the United Kingdom, the United States and Canada. (CKNW, The Canadian Press)
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