My son Burt is missing.  I am frantic with worry, because he is only 3 or 4 years old.  When he turns up, I ask him where he was, and whether he has taken his medicine, which he has with him in a plastic vial.  He doesn't answer.  I ask him again and he still doesn't answer.  I become very annoyed at his lack of cooperation and tell him he will not give him anything to eat until he talks.  That threat doesn't get him to talk either.  Eventually he starts crying bitterly, and I comfort him, but I still want to know the answers to my questions.