SUBREDDIT: r/relationships
TITLE: Me [30F] with my sibling [28M], obvious disparity between abilities causing friction between otherwise happily-married parents
POST: My brother is a great guy, but he's always struggled intellectually, athletically and professionally. For a long time, I think our parents or, at least, our mother, attributed this to having been born with complications but his issues have yet to resolve as an adult.

In contrast, I am a quick learner who finished college quickly and am successful in my career and athletic pursuits. I don't say this to gloat, but to make a point. 

The disparity between my brother and me is glaringly obvious. Everyone jokes that I take after my father who is incredibly successful is *his* career and athletic endeavors as well. My father's family members are all in this same vein - smart, successful, indomitable. 

My mother's gene pool is not quite so hearty as she comes from a long line of "simple" people who are just like my brother: kind-hearted, well-liked but otherwise not so bright. As such, she blames herself for my brother's lack of ability. 

This causes friction between my parents which I only just learned about, though I'd suspected it for a while. Mom blames herself which Dad doesn't want, because - really - it's neither of their faults (even if my mother has coddled my brother as a means of protecting him from the world for which he is so ill-equipped to navigate on his own). 

Mom gets upset when Dad gets frustrated with my brother. Brother and I aren't close because we don't share common interests (and possibly because I've always been something a reminder of what he's not). None of us asked for any of this and I don't know if there's anything I can do to remedy the situation.

I'm sure we can't be the only family like this. I feel like you see it regularly in movies/tv: "accomplished daughter, slacker son, frustrated parents". DAE have any ideas as to what I could do to diffuse this? Or do you think it's just going to simmer along until we accept our family fate?
TL;DR: 
Me - successful, female, 30 - with slow-to-mature, possibly undiagnosed learning disabled brother (age 28). Parents frustrated with son. Mother blames self. Is there anything I can do?