David was able to suppress these thoughts until the day he had his "psychotic episode." During Tessara and Samantha's murders, David says his psychosis made him think of his actions as "tasks." "[I thought], it's a task I have to do. It's not anything related to, 'These are my daughters. These are lovely children.' It's just a task," he says.
In this state of depression, David says he also convinced himself that if he killed one girl, he'd have to kill both. "They were twins and in parenting them, you do things together," he says. "So in the psychotic state I was in, I couldn't show favoritism. ... It's just sick."