Calvin and Hobbes by Bill Watterson for May 15, 1986
Transcript:
Mom: Oh, Rosayln, you're here! Good, come in! We really appreciate your coming on such short notice. We've had a terrible time geting a babysitter for tonight. Ha ha. Maybe little Calvin here has gotten himself a reputation. Rosalyn: Ha ha. You have the half up front? Mom: Yes, let me get my purse...
This is the first comic introducing her! Yay!