“Fred, you next,” the plump woman said. “I’m not Fred, I’m George,” said the boy. “Honestly, woman, you call yourself our mother? Can’t you tell I’m George?” “Sorry, George, dear.” “Only joking, I am Fred,” said the boy, and off he went. His twin called after him to hurry up, and he must have done so, because a second later, he had gone — but how had he done it?
