Ethan Crumbley opened fire inside Michigan's Oxford High School on Tuesday, killing four fellow students and injuring seven.
Ethan has been charged as an adult with murder, terrorism, assault and weapons possession, and authorities believe the attack was premediated. His parents, James and Jennifer Crumbley, have both been charged with four counts of involuntary manslaughter.
As authorities seek to hold James and Jennifer accountable, many are wondering if Ethan's high school also dropped the ball and missed warning signs.
Read more below.