Pardeep Singh Kaleka has examined how people across the United States react to mass shootings. Seven years ago, a white supremacist invaded a Sikh religious center in Wisconsin and killed six people, including Kaleka’s father. His father died holding a knife he had tried to use in an attempt to stop the shooter. Now, whenever a gunman attacks another U.S. city or town, Kaleka leaves a supportive message on social media. Often times he will then travel to the affected community to help others face the pain he shares. Kaleka has been to Newtown, Connecticut, where a gunman killed 26 people at Sandy Hook Elementary School in 2012. Kaleka also has visited other communities affected by violence. “We’ve become kind of a family,” he told The Associated Press. The number of U.S. mass shootings has increased in recent years. The most recent attack happened last Friday, when a gunman killed 12 people in Virginia Beach, Virginia.