psychologist. Laura Moser Sage Kirkpatrick Laura Moser is Dexter and Brian's biological mother. She was involved in the drug trade and had a habit of painting her fingernails in different colors. She and three others were sawed into pieces in a shipping container as her two sons watched, causing their murderous urges. In the second season, it is revealed that Laura had an affair with Harry Morgan and was working as a police informant, trying to get evidence against Santos Jimenez's boss. She is not named in the books and no such revelation is made. Laura appears in Season 3 during two of Dexter's visualizations of Harry. While Dexter is tracking a victim on a cruise, she sits with Harry as if they were vacationing together, much to Dexter's discomfort. In the season finale, she appeared, again with Harry, at Dexter's wedding appearing to be happy for her son. Her mugshot was also briefly seen on Debra's desk as she investigated her father's infidelity. When Debra's investigation of another informant (coincidentally the file before Laura's) leads her to discover her father having multiple affairs with informants, she angrily gives up on her search; Dexter takes this opportunity to shred Laura's file and her photo, but is unable to go through with the photo ("I can't let her be cut up again") and keeps the upper half in his desk. Despite Dexter's efforts, Debra and a former informant locate Laura's house, which ultimately links Dexter to Laura, and to Brian. Brian Moser Christian Camargo Brandon Killham (child) Brian Moser (alias Rudy Cooper, moniker The Ice Truck Killer) is Dexter's biological older brother and the main antagonist of the first season. As children, both brothers witnessed the chainsaw murder of their mother, Laura, and afterward were left for two days with her body in a shipping container until the police found them. The memory lay buried in Dexter's subconscious for years until a therapist unknowingly reawakened the memory. In the aftermath of the killings, Harry Morgan, the officer-on-scene, adopted Dexter, while Brian was left in the state's care. Brian believed that Morgan did not want anything to do with him because he saw him as a "fucked up kid". Brian suffered severe psychological trauma due to the experiences in the container and was left in a mental institution, where over time he became a violent psychopath, resulting in him also becoming a