Carl the Collector Episode 14 A Collection to Get Rid Of/The Button Collection >For the birthday of Sheldon's mother, Sheldon wants to give her a mug made by Maude. To keep it a surprise, Carl agrees to take of the mug at home until Sheldon visits to retrieve it. While entering his house, Carl accidentally drops and breaks the mug. Carl blames himself, declaring himself a bad friend for his mistake. Although distraught upon being told, Sheldon points out that Carl's remorse makes him a good friend. Heartened by Sheldon's words, Carl helps Sheldon turn the pieces into a mosaic tray to give to Sheldon's mother, contributing yellow buttons from his button collection.