How could this specific case realistically have been prevented though?
I mean, from what we know, this girl almost certainly took her father's unattended gun and used that to shoot up the school, It's not like a background check thing can solve this specific case (no doubt it could for others though). Like should there be laws enforcing parents to keep guns away from certain kids' reach (those with mental health problems or those under a certain age) unless they're supervised? (it sounds like a good idea to me TBH) And how do we enforce those hypothetical laws? (serious question) Or maybe more investment in mental health services for troubled kids as well?
Gun safeA gun safe is a safe for one or more firearms and/or ammunition for guns. Gun safes are primarily used to prevent access to unauthorized or unqualified persons, for burglary protection, and, in more capable safes, to protect the contents from damage during a flood, fire, or natural disaster. Access prevention is required by law in many places, necessitating a gun lock, metal gun cabinet, or gun safe. Gun safes have largely replaced the gun cabinets made of fine stained wood with etched glass fronts used for display that were commonly used decades ago, although some gun safes are made to resemble such gun cabinets.
See also:
Gun Safety - StorageIf you can afford a firearm, you can afford to store it safely. If you don't, you should be charged and forfeit the right to own firearms.