In the episode of Hey Arnold where Helga leaves a message on Arnold's answering machine, she realizes that doing so wasn't such a good idea, and so she sneaks into his house in attempt to get rid of the tape. As Helga awaits in the air-vent, Arnold and his friends come running through the house. Arnold and Gerald stop to speak to Grandma. Arnold is holding an ice cream bar and Gerald is holding an ice cream cone. ( or vice-versa) The two boys then leave to join their other friends in Arnold's room. After Helga retrieves the tape, she finds herself falling throught the airvent and ending up in Arnold's room. All of the boys are puzzled, and as the screen moves over each kid, you can see that Arnold and Gerald are holding different ice creams from when they were downstairs!