CNN  —  Paul Kemp, a 64-year-old who lives outside Portland, Oregon, bought his son Nathan his first rifle for his 16th birthday over a decade ago. Nathan had notched his first hunting kill, a squirrel, at age 7, and the Kemp family enjoyed their time hunting together over the ensuing years. When his son turned 16 in December 2012, Kemp believed he was responsible enough to have his own firearm. “Hunting was a family tradition. Everybody enjoyed it,” Kemp told CNN in a phone interview. “Call it,