Calvin and Hobbes by Bill Watterson for August 10, 1989
Mom: What kind of dinosaur did you say this was? Calvin: It's a stegosaurus! Mom: He looks pretty ferocious. Calvin: No, he was a plant eater. The tail wpikes were for self-defense. Mom: Oh, did tyrannosaurs fight these? Calvin: Of course not, Mom! Tyrannosaurs came millions of years later! Look, try not to embarrass me when we go inside, Ok? Dad: Why are we going here if he already know everything?