I've read interviews with both of their mothers, and it seems that they have spent their lives being told they are 'special' and way beyond the little people. On another level where they are almost worshipped.
I'm not enough of a psychologist to unpack that, but it does seem to lead to incredible levels of narcissism.
Both are unable to accept any form of criticism, which they perceive as rejection. They reply with an assertion of their superiority. Neither seems to believe that normal societal rules apply to them. They are literally above the masses.
Alexander Johnson is similar, but in his case the perpetrator was his father, which I suspect makes things a great deal more complicated.