Opinion: What research tells us about the aftershocks of school shootings

I was a 17-year-old high school senior when the unthinkable happened: Two students at Columbine High School shot and killed 13 people before dying by suicide. News of the mass shooting rocked the country, and I still remember the adults who tried to reassure me by noting the infrequency of such an event — it was an anomaly, they said.