defanging the snake as they grow
I have a 3 1/2yo and a 17 month old. The older knows she must ask daddy before touching anything (when not they're not locked up and thus out for cleaning). The younger does not see or touch know of ect., Post cleaning opportunities allow her to revisit a few of the basic 4 rules in young child form as she interests (I've not tried to force any such info on a disinterested 3yo). She must ask before touching anything firearms related and does so right down to the toolboxes and various supplies within when I have it out. I have allowed her to hold something after she appropriately asks, with no magazines and actions open and a repeated reminder not to touch triggers and to point at a deemed safe direction (not people or herself), I guess the older folks call it "de-fanging the snake". Taking the mystery out of it. This seems to work well thus far, and is normal procedure for both of us. Firearms are treated like other devices and tools that are potentially dangerous and demand respect and help (garage stuff, tools, gas ovens, ect.,) Their unique personalities dictate what I will try and teach at what point as well. I will not\would not allow my young kids to handle a loaded mag, or even just rounds!!! Again, this child is the compliant very observant asks questions type about parts and names ect., My plan is to continue such that she may one day when is much, much older become a responsible owner\shooter. Until well after then things stay locked away and require my assistance\permission.
I then built her an oak rubber band gun and reinforced the same rules. She asks, and practices not touching trigger, knowing her target and beyond ect., Smart little girl. Very compliant have not had issues and we'll aim to stay consistent. She knows mommy and daddy follow safety rules and when she is older and wants to shoot she will have to do exactly the same. She does however have squirt guns that are treated as simple toys in the yard and says "they're toys, but dad's are not".
Regarding HD situation: with little ones I think its just gotta be locked up. I have kept a loaded mag or weapon in a separate locked and secured case. Yes, that's a pain, slower and inconvenient but its necessary. For handguns you may look into some of those real quick access mini safes to keep by a bed, some have small profile to even fit inside a night stand drawer.