Wall Street Journal social media director Liz Heron notes that the life cycle of viral content is composed of two phases: "Uncritical mass sharing" followed by "semi-informed backlash."

Three days before 20-year-old Adam Lanza killed his mother, then opened fire on a classroom full of Connecticut kindergartners, my 13-year-old son Michael (name changed) missed his bus because he was wearing the wrong color pants.