Wow. One sane person, at least.
I would love to own several guns, but my son would be likely to cause some kind of incident, as he is seriously impulsive and Houdini, to boot. I won't take the chance that he might endanger my other children. A large dog will have to suffice for a few more years until he is out of the house.
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) :)
Why stop at one? I own six. An old 30/30, a 12 gauge shot gun, a .410 shotgun, two twenty gauges, and a handgun.