George Reeves was always cautious when interacting with children who were fans of Adventures of Superman, because on multiple occasions they thought he was really Superman and tried to test his invulnerability. 

Most often, kids would come up to him and try assaulting him, but what one kid did really blew away the rest. At one appearance in costume, George Reeves greeted a young boy who quickly pulled a pistol out and pointed it at him. The boy had taken the pistol, a Luger, from his home. 

It had belonged to his father, who had brought it home after World War II. He wanted to shoot Superman to see if he was really invulnerable like on the TV show. Reeves didn’t want to say he wasn’t really Superman, because it would have ruined the entire appearance and possibly upset the child. 

He managed to get out of it by convincing the child if he shot him, the bullet could bounce off him and hurt someone else.