Similarly, Elly cannot seem to ever quite realize that her pets do not, cannot and will not understand English as well as a human being does; since she cannot take to heart her sister-in-law's advice about how, despite their having learned to associate certain sounds with certain things, their facial reactions don't actually mean that they understand what she's saying. You and I know that when a dog recoils in surprise and makes a submissive gesture when someone yells 'Bad dog', they're simply following their instinctive response to submit whoever's the loudest; she sees it as them thinking 'Busted!'
As you might expect, the need to alter memories to fit preconceptions is pretty much the real legacy John and Elly are handing down to their children. As by way of example, no matter how many times Liz is told that her lack of attention to her surroundings and non-existent ability to focus is what held her back scholastically, she remembers herself being singled out by some fink.
Finally, Mike can never seem to learn that bad things happen to other people too and they feel pain just as he does because other people aren't really real to him; he never quite realized that the world is not himself because he was raised by self-absorbed twits to be a rampaging egomaniac.