Regardless if you like guns or hate them, you should be proficient with some of the basics. Your kids should be proficient in the basics as well, if the basics are obeyed there would be no accidents with firearms.
Treat it as if it's loaded. It's irrelevant if you've checked 3 times or 50 times, treat the firearm as if it's loaded. There are no exceptions to this rule, if you have a firearm it's loaded, don't point it at anything you wouldn't be okay to part with.
Never point a firearm at something you're not willing to destroy. You can fix your wall, door, window, ceiling, etc., but you cannot fix the hole in your dog, wife, or kid. Regardless if the firearm is loaded, never point it at something you're not willing to put a hole in.
Keep your finger off of the trigger. This is the rule that keeps your floors, walls, and ceilings in good shape if you follow the first 2. Some firearms have a very light trigger, keep your finger away from it unless you're 100% ready and sure that you want the thing to fire.
These are the basics that everyone should know. These should be taught in school. If your wife doesn't know these teach her. If your kid doesn't know these teach them. If your friend doesn't know these teach him. It's irrelevant if you own a firearm, hate firearms, love firearms, whatever, you should know these basic things. Like I said previously, if these rules were followed there would be no accidental deaths with firearms involved.