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Lampkin hates the cat, but keeps him in his wife's memory. He typically carries Lance around with him in a bag, telling Laura Roslin that he does not "bite or scratch" like his wife did. As Lance scrambled out, Lampkin may have used the diversion created by his animal to steal Roslin's glasses.
Later, when boarding Sharon Agathon's Raptor, Lance escapes from his bag, jumping out of the Raptor before its door could shut. Chief Galen Tyrol and his deck gang manage to corral him, but not before Tyrol discovers the makeshift bomb on the Raptor's undercarriage, thus thwarting Aaron Kelly's plan to kill Lampkin (TRS: "The Son Also Rises").
An innumerable number of weeks prior to Laura Roslin's abduction by the Cylon rebel's Hybrid, Lance is killed. Lampkin claims that "those debased dregs of humanity" in the Fleet were responsible for this act. As a result of his death, Lampkin became withdrawn until approached by Lee Adama to aid in a search for interim presidential candidates; Lampkin talks to an idealized version of Lance during these proceedings, while the actual cat's remains were kept in a duffel bag (TRS: "Sine Qua Non").