Dilemma:
I support harsher penalties for gun owners who don't secure their guns and they wind up being used in these horrific tragedies. Not murder charges, as Badger notes, murder is a very specific charge and it doesn't apply, but harsh penalties with severe sentencing nevertheless.
I also have one pistol that's pretty quickly accessible to me in our bedroom, and my reasoning is that's why we have that one, for midnight burglars when I can't waste time getting into a safe. (That's never happened and hopefully never will, but better safe than sorry and all that.) Where it's kept, a child of less than 12ish years or so could not retrieve it, and it's hidden from view and not anywhere we think would ever make anyone assume "Oh, I bet there's a gun there, or any object, I should check that out." And nobody even knows about it except for me and my wife. Yet I consider it quickly and easily retrievable for me, should I ever need it.
We don't have kids in the house. Just one stepson in his 20's. I still don't know if we did have kids if it's a good idea. I also don't want all my home defense weapons in a safe. I mean, if I wake up in the middle of the night to trouble, the intruder already has the drop on me, I don't want to be at a further disadvantage. I don't know if I have a good solution or not. It's worked for us with no problems thus far, but like I say, we don't have kids.