Calvin and Hobbes by Bill Watterson for February 18, 1989
Mom: Rosalyn? We're home. Hi, Rosalyn> Did you have a quiet evening? Did you get your studying done? ...no, huh? Rosalyn: I'm sorry, but tonight is really going to cost you. Dad: You're sure no one else in this town will agree to baby-sit Calvin? Mom: Maybe you would like to spend a week on the phone!