People like you make bad assumptions. You don't know what kind of parents he has. His parents could be the type that taught him responsible use and respect of guns. His parents could be the type that take him to a range every chance they get. His parents could be the type that put him through a gun safety class. That doesn't matter to you, though. All you see is a 13yo with a gun in his room. Based on only that, you assume his parents are the type that don't look after their kids and don't care what they're doing. You assume that his parents are irresponsible enough to not know that their 13yo has a gun.