I think it depends on how old timmy is, I was able to get a handle on the hammer fully at a very young age. probably 4th/5th grade, previously I was able to command a small sqaud of sqauts with somewhat limited efficiency. I remember buying my friends orks from his box set about then. How young could a kid get on age of sigmar really?
people often have strange double standards for what "adults" and "children" do and dont do sometimes for the right reasons other times based on blind reaction.