The wise [son], what does he say? "What are the testimonies, the statutes and the laws which the L-rd, our G-d, has commanded you?" You, in turn, shall instruct him in the laws of Pesach, [saying] `one is not to eat any dessert after the Pesach-lamb.'*To this passage my Grandma always comments: "And that's why we don't eat lamb!"
Hag Pesach Sameach, friends.
(* My family always uses the Maxwell House haggadah; since I didn't have mine handy, the quote is from Sichos In English.)