He escaped from a completely broken family

From the description of the father and mother beating him while laughing at him, I can say with some certainty that the father was not just scarred from his own upbringing. Getting joy from it is taking it a large step past that. The fact that the mother joined him in this torture shows that they were two of a kind, and no one said anything about her having an abused childhood. It seemed that the brother and sister, even though they were both married, still lived together (doesn't sound too healthy). By doing nothing about their younger brother's abuse, they were basically enablers of their parents' horrible acts. Allowing their father access to the brother's son was stupidity in its worst form. Why was the father not arrested when he pushed a toddler down stairs and crippled him? Dirk certainly had a lot of mental scars from his childhood, but his siblings had it even worse, as it seems as though they were under the thumb of the parents even when they were married adults. And where the hell were the sister's husband and the brother's wife when all this abuse was going on?