S1, E4: "Double Trouble":  Dexter and his cloning machine overheat when Dee Dee and her friends clone and re-clone themselves for Laboratory fun-time. / "Dexter's Lab": A Story" When Dexter takes in a lost Labrador Retriever, he decides to enable the dog to talk. This backfires when it turns out that the dog has very little of interest to say. / "Changes":  A young genius, Dexter, invents a device which can change a person into any animal. Trouble starts when his pesky sister Dee Dee wants to try it out. This was the first Dexter short ever created.