I’ve brought my child (a couple years younger than yours) twice because he wanted to see what I do at the range, and to have the wife try some shooting.  The rso’s were ok with it as long as he did not handle any firearms (obviously).  I did have eye and ear pro on him and we went to the silhouette side and rifle side and we kept him behind the firing line while the wife and I took turns at the bench. 

Big takeaways, children are very observant and just by watching he got basic understanding of keeping a muzzle down range and always having eye and ear pro while shooting.  The proof was one day he set up a “shooting bench” for his bolt action nerf rifle and kids work bench and a foot stool to sit on. He even came to ask me for his ear muffs and safety goggles so he can shoot targets at his gun range .  When He was done with the setup it was exactly like koko head with the nerf rifle facing down range and some Ammo on the table and a target cardboard box “down range”.   My plan is to instill firearm safety from a young age so it will be natural when they are old enough to handle a firearm.

I registered a couple of Poly 80 handgun frames earlier this week with my rifle permit. My made up serial numbers used four letters with my initials and three numbers. I try to make it easy for HPD. They treat me well.