I'm leaving Francis out of this, since, as he's away from home a lot of the time, there's not as much interaction between him and his brothers as there is between those still at home, and also because I think Malcolm, Reese and Dewey all seem to get on well with him and look upon him as a role model (with Malcolm maybe slightly more so than the others.)
I'm also not including Jamie because I've never seen an episode with him, and because he's probably too young to have established a relationship with any of his brothers.
Out of the episodes I've seen (which is all of Season One, one from season two, which was an episode where the family (except for Hal) fought with their new neighbours, and about four from Season Four) I would say that Malcolm and Reese would seem to be the closest. I know they fight a lot, but they are the closest in age. Reese seems to use Dewey as his punchbag, and while Malcolm doesn't seem to pick on Dewey as such, he seems to find him annoying and whiny. Since he and Reese are older, although Reese is annoying and a bully, I would think that those two would do more stuff together and be closer.
Of course, that's just my opinion, and I suspect you've all seen more episodes than I have, so, what do you guys think?
I'm also not including Jamie because I've never seen an episode with him, and because he's probably too young to have established a relationship with any of his brothers.
Out of the episodes I've seen (which is all of Season One, one from season two, which was an episode where the family (except for Hal) fought with their new neighbours, and about four from Season Four) I would say that Malcolm and Reese would seem to be the closest. I know they fight a lot, but they are the closest in age. Reese seems to use Dewey as his punchbag, and while Malcolm doesn't seem to pick on Dewey as such, he seems to find him annoying and whiny. Since he and Reese are older, although Reese is annoying and a bully, I would think that those two would do more stuff together and be closer.
Of course, that's just my opinion, and I suspect you've all seen more episodes than I have, so, what do you guys think?