Origin of Nite-Owl's Submissive Nature

One of Dreiberg's primary traits is his submissiveness. During Watchmen, he allows people such as the Comedian to trample over him, and is generally a passive person. I was wondering if there was anything depicted during the story that explains why he is like this. (And please don't tell me it was explained in the prequels, I'm going as far as I can to believe that they don't exist)

abusive father and distant mother

Was that in the prequel?

maybe. maybe not.