My kids are smart as whips. They are grown now, and one has made me a grandfather. But I had guns in the house the entire time they were around, and before. I never locked them up, nor the ammunition either. But if I'd has one that rambunctious, I probably would have. My girls were taught how to shoot them at a fairly early age, as soon as I got the first .22 handgun in fact in the case of the older one. (I was a shotgun only type, until "corrupted" by my wife's grandfather (which got me the 10/22 Ruger) and her father (first the .22 S&W handgun and then the flood gates opened, starting with the 1911A1) :)
My Daddy used to take my brother and I target shooting..in California, no less! : )
I have coveted my Mom's Colt revolver for over twenty years now. She shows no signs of passing it along, although I have never seen her shoot it.
I just can't take any chances with my son, though.