Ok, but most of us are more than convinced that aside from Martin appearing to have ADHD, Chris probably has OCD.
Guy just look at the man, there is no chapter in which he does not highlight his order. And yes, maybe he just likes order and that's it, but sometimes when Martin has something messed up, he is seen as anxious (obsessed) and always has his things organized by color, size, use or in the cases of discs, by habitats (compulsion).
In conclusion, both brothers have disorders that literally do not allow them to live 'together' so to speak, Martin, due to his hyperactivity, can stress Chris too much, making him constantly angry with him and his anxiety only grows, both are aware of this and well, it is something that is seen in the series, neither of them is very attached to the other for the simple fact that they get stressed with the other because of their disorders