I don't have children but I think I probably was one back in the day and I shoot a lot of skeet squads w/ kids getting a taste of the target sports and maybe some hunting prep. The Daly bantamwgt/lgth. 20 sounds like the ticket if you can find a load that will cycle it and not kick the snot out of the kid. If they single load, even that doesn't matter. I don't know where the bolt release is on the Daly; the ones with the pushbutton (not 1100) don't appear to present that much of a mousetrap hazard.
The safety protocol generally and for the specific gun has to be drilled in. I get painted all the time by 50 and 60yr. olds taking their O/Us out of the rack and opening them. If you never want to sing the "I didn't know . . ." tune, the gun should come out of the rack with the muzzles in the air when it's opened. So safety-wise there is no special gun which will make young or old heads work optimally.
9 yrs. old is pretty young imo but I have seen a runty 10 yr old with desire and Dad's trap vest down to his knees do pretty well with a heavy Citori. Conversely some of these gangly computer cowboys who can't take out the trash without a dolly need something that a short light gun won't give them.
