“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 tellI’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?