So, I’m kind of wondering if Rick’s deep attachment to Morty has to do with availability?
We know from the pilot that Jerry is an ableist asshole who probably values the idea of a son a whole lot more than he values Morty, the son he has. Summer is Beth’s favorite child, and also older and more assertive - she would be more likely to push back against Rick, and Beth would be more likely to notice Rick’s abusive behaviors and put a stop to them.
When you consider the Morty of season one, presumably early in their adventures, it’s clear that he really doesn’t put up much of a fight against Rick. He’s stunningly easy to manipulate (even later in the show), and for whatever reason, even through his growing resentment, Morty is loyal to Rick (though I think that is shifting).
As far as valuing Morty over Beth, well, that’s all about control. Beth is smart. Rick has emotional power over her, sure, but she’s a grown ass, intelligent woman. Rick sees her as a threat. Morty isn’t.
At least, not yet.
Rick needs somebody who is young, insecure, dumb enough to pander to his genius, but competent enough to survive the multiverse. Nobody has ever noticed Morty, and nobody notices him now. Too, Rick probably justifies his treatment of Morty by their familial relationship - Morty is Rick’s grandson, and therefore, “his” to groom and corrupt.
I’m probably missing soooo much here, though.
