Calvin and Hobbes by Bill Watterson for June 11, 1990
Calvin: I don't feel so good. Mom: You don't look so good. Let me feel your forehead. Calvin: Summer vacation started! I can't be sick! Mom: Your head's hot. I'll get the thermometer. Calvin: No! I refuse! Forget it! I hate thermometers! I still don't believe her that these things take two hours to register. Mom: Now be nice and quiet and I'll check on you this afternoon.