Why the hell parents didn't get psychological help? Younger son was having nightmares and ...

Because their parents are morons with a capital M.they probably wanted to keep everything from becoming public so they descided not to seek treatment for their mental trauma.Their thoughts were like if we don't talk or acknowledge it doesnt exist

So unhealthy. If you don't clean out the rot it spreads till every things destroyed. They're not just morons with a capital M as you said this makes them bad parents. I would even say its a form of negligence.

i guess that's what happens when weigh money & prestige more than health.

*you

if i'm not mistaken both brothers did get psychological help (remember both of them alluding to the fact), but for some reason it either didnt take or the psychologist they saw (they didnt go together, i think - again don't know to say exactly, cause it was implied, not really talked about) wasn't very good at his/her job, or they were too fixated in blocking (each for their own reasons) the incident away.

Yeah, you are right. But this doctor didn't do a good job apparently, because both of them are still traumatized.

for sure A rotten job. it's just that u blamed the parents and even i did so, but thinking about this whole situation i'm pretty sure anybody would feel helpless, and the fact that they r grown-ups doesn't mean they have the answers and even the fact that they r rich didn't help, cause i'm sure that they went to the best doctors psychological and medical and the fact that both brothers r still f*cked-up means that they didnt know what else to do and just gave up. not that that's a good things but what else could they do... complex situation - me personally feel sorry for everyone involved even the nutter that commited suicide.
* on an off note - love this manga ╮(￣▽￣)╭

Maybe you are right. But we don't have enough information unfortunately. Anyway, it's just so hard watching both of them struggle.