I have been in several homes where one cannot get more than ten feet from a loaded gun (no lock, round in the chamber, safety off). I always feel safe in those homes, and I have never seen a kid touch a gun without permission in one of those homes.
I was raised in a house like that; firearms in corners behind outside doors, in gun racks in the house and in pickups- then pistols in nooks and crannies. I have no idea how dad trained us kids to leave that all alone, was too little to remember that training but would have never touched any of those firearms or anything related to them in a million years. I remember him teaching us safety and how to shoot when we were older but don’t remember the early toddler training we had to have. I was not necessarily afraid of firearms- just knew absolutely that I had to leave them alone.
I have two children at home, ages 13 and 14, they know about "Dad's guns", but I have two great grand children visiting for 2 weeks, so for 2 weeks, it's outta sight, outta mind.
I can't teach them enough in 2 weeks to be assured that they would leave them alone. They are ages 4 and 6.