A 16-year-old Pennsylvania boy, already charged with aggravated assault in the shooting death last month  of his 8th-grader girlfriend, has now been charged with involuntary manslaughter. Erie police say Riley R. Shearer “unintentionally” killed 15-year-old Audrey Maria Kellogg but acted with recklessness or gross negligence, according to the Erie Times-News. Kellogg died from a gunshot …