I grew up learning how to shoot in fact I wasn't much older than that when my father let me have shoot his rifle. By 10 we were going out alone and shooting Rock Chucks. As long as you teach your child that guns are not toys then its ok.
I grew up with them laying all over the kitchen table and in nearly every room of the house. It was never a big deal to me or my siblings. We knew that we could just ask one of our parents and they would take us shooting anytime we wanted. DS will be raised the same way. He's not quite 4 yet but in the next year or so I'll get him out there. In the meantime our guns are secured.