IMO there certainly is dysfunction in the whole family. No doubt.
Casey appears a narcissistic BDL PD to me, with sociopathic tendencies.
Her inappropriate affect and totally off-the-mark emotional responses in situations raise those flags for me. She'd be interesting to do an assessment on for sure.
Regarding "can a person just be "evil" : there is a reasonable body of coherent evidence that sociopaths have a dysfunction of the frontal brain. Why and when this dysfunction appears is totally unknown, thus far.
Quoting from some studies:
Robert Hare, PhD., says that the personality of a sociopath (psychopath) is essentially set in stone, so to speak, by adulthood, and incredibly hard to change.
Hard to change, not impossible.
Recent research on the disparities of brain function in psychopaths/sociopaths yielded some startling results:
Structural and functional hippocampal abnormalities have been previously reported in institutionalized psychopathic and aggressive populations. This study assessed whether prior findings of a right greater than left (R > L) functional asymmetry in caught violent offenders generalize to the structural domain in unsuccessful, caught psychopaths.
Methods:
Left and right hippocampal volumes were assessed using structural magnetic resonance imaging (MRI) in 23 control subjects, 16 unsuccessful psychopaths, and 12 successful (uncaught) community psychopaths and transformed into standardized space.
Results:
Unsuccessful psychopaths showed an exaggerated structural hippocampal asymmetry (R > L) relative both to successful psychopaths and control subjects (p < .007) that was localized to the anterior region. This effect could not be explained by environmental and diagnostic confounds and constitutes the first brain imaging analysis of successful and unsuccessful psychopaths.
Conclusions:
Atypical anterior hippocampal asymmetries in unsuccessful psychopaths may reflect an underlying neurodevelopmental abnormality that disrupts hippocampal-prefrontal circuitry, resulting in affect dysregulation, poor contextual fear conditioning, and insensitivity to cues predicting capture.
And:
"Research with animals has shown that the right orbitofrontal cortex is involved in fear conditioning. For instance, when a rat is punished with an electrical shock every time a light blinks in its cage, it develops a fear association between the stimulus and the punishment. Normal humans learn very early in life to avoid antisocial behavior because they are punished for it and because they have the brain circuits to associate fear of punishment (feeling emotion) to behavior suppression. This seems to be a key element in the development of personality. When there is no punishment, or when the person is unable to be conditioned by fear, due to a lesion in the orbitofrontal cortex, for example, or due to lowered neural activity in this area, then it develops an antisocial personality.
We have now a direct way of visualizing brain function, which has lead to a remarkable explosion in our knowledge about the inner workings of the psychopath's brain in the last two to three years:
Images of Violence
Functional images of the brain, such as those provided by PET (positron emission tomography) have been used to corroborate the existence of neurological deficits in the frontal lobe in sociopaths. PET shows computer reconstructed transversal sections of the brain, showing in vivid color the level of metabolic activity of neurons. This is achieved by injecting radioactivity-marked glucose molecules into the patient's blood flow and seeing how much of it is incorporated into living brain cells. The more active the cells are (when they are processing information, for example), more intense will be the image at that point (see my article "PET: A New Window Into the Brain", in the first issue of Brain & Mind Magazine, to understand better how this technique works).
Positron Emission Tomography (PET) scanner obtains sectional images of the living brain, using color to depict degree of activity. Crump Institute for Biological Imaging, University of California at Los Angeles.
Using the PET technique, American medical researchers Adrian Raine and colleagues have been studying murderers, with startling results. They found that 41 murderers have a much decreased level of brain functioning in the prefrontal cortex than normal persons, indicating a deficit related to violence. In other words, even when no visible pathological alteration was present, frontal damage was apparent by a abnormal lower activity of the brain in that area. "Damage to this brain region," Raine noted, "can result in impulsivity, loss of self-control, immaturity, altered emotionality, and the inability to modify behavior, which can all in turn facilitate aggressive acts."
Other abnormalities observed by the PET study of the murderers' brain included reduced neural metabolism in the superior parietal gyrus, left angular gyrus, and the corpus callosum, and abnormal asymmetries of activity in the amygdala, thalamus, and medial temporal lobe. It is probable that these effects are related to violence and criminality; because some of these structures are part of the so-called limbic brain, which processes emotions and emotional behavior (please see "Limbic System: The Center of Emotions" in Brain & Mind Magazine)"
