The parents really don't even know their own children. They can't see past the reflection of themselves.
Isn't that the truth?! Even now, some 30-odd years later and despite the fact that my sister makes more than I do, climbed the ladder higher than I did etc, my folks still make snide comments about her. I'm sure they make snide comments about me as well - that I didn't do what I could have done to be more perfect. Sometimes it comes out (usually when drunk), but it usually shows up in unintentional statements where they can't even see what they're saying.
My father, no matter how many times I've told him that it is not what I want, still pushes me to be him - to be ambitious, to strive for perfection, to be "brag - worthy". I am not ambitious, I like a quiet life, if I can pay my bills and feel like I'm useful to someone or in my job, that's enough for me. That's my comfort zone. I've stopped arguing with him, and instead tell him to brag on my sister if he wants someone to brag about, she's earned it (and she is ambitious).
He still can't see that I'm not him and that she's more than he thinks she is. When sober, he'll deny this, but when drunk? Then all the old meanness and pettiness comes out - funny enough, just like his father did to him. And down the family tree it seeps.