It's stated that Archie hasn't spoken to Fred in twenty-nine years, but on season three's "Lionel Steps Out" Archie talks to Fred on the phone and in a friendly manner, unlike what is revealed in this episode.
In the season six episode "Archie Finds A Friend", Archie Bunker (Carroll O'Connor) states that he is an only child. However, it is revealed in this episode that Archie has a brother.