Over 100 children (aged 0-14) killed unintentionally with guns each year 

An article in the journal Injury Epidemiology by David Hemenway and HSPH graduate Sara Solnick (Professor at the University of Vermont), finds that the Vital Statistics data (e.g., WISQARS) underestimates the number of US children killed unintentionally with firearms (often reporting accidental shootings as homicides).  Using data from the National Violent Death Reporting System, Hemenway & Solnick find that of the 100 or more cases each year, in about 1/3 of the instances the child unintentionally shot himself, and in 1/3 the child was shot by another child (usually a brother or friend).  In half of the remaining case the child was accidentally shot by a parent (i.e., the dad).  These cases represent only the tip of the iceberg in terms of accidental shootings as there are far more non-fatal shootings than deaths.