Or: "Don't shoot strangers."
Or: "Shoot only family."
Take your pick. These are all things my bro-in-law said to his daughter one day during our DW trip. Each child got to pick out a little something from one of the shops at the park and my niece chose a cool looking toy gun. Or rifle. Not sure...Anyway, she was having lots of fun with it but daddy just wanted to make sure no one got offended. He's really into gun safety. Her twin sister, on the other hand, was happily playing with her princess purse or doll or necklace (can't remember exactly what she chose) and was quite oblivious to the gun show. Now, these two cuties are very shy and rarely talk to someone until they feel super comfortable with that person, so just picture the little shooter, head down and eyes up, a shy smile on her face, walking around quietly 'shooting' whatever she felt needed shooting. I don't think anyone would have minded being shot by her at all.