Fred dismantled his oldest son by devaluing and degrading every aspect of his personality and his natural abilities until all that was left was self-recrimination and a desperate need to please a man who had no use for him. The only reason Donald escaped the same fate is that his personality served his father’s purpose. That’s what sociopaths do: they co-opt others and use them toward their own ends—ruthlessly and efficiently, with no tolerance for dissent or resistance.
Fred destroyed Donald, too, but not by snuffing him out as he did Freddy; instead, he short-circuited Donald’s ability to develop and experience the entire spectrum of human emotion. By limiting Donald’s access to his own feelings and rendering many of them unacceptable, Fred perverted his son’s perception of the world and damaged his ability to live in it. His capacity to be his own person, rather than an extension of his father’s ambitions, became severely limited.