Now do that with Wanders one and turn it upside down. OMG IT'S THE SAME! Maybe they are related too!!!
Common dude. They're all from the same culture so they all wear the same "similar" (read: not the same) things, there's no relation.
Are you serious? How is it the same color scheme? Unless if by that you mean, they both have colors...
No, I mean the same colors. Pink where its pink, white where its white, grey where its grey. Emon's has more negative space, and the colors overall are more muted in SotC than Ico, but they are the same colors.
I don't know why you feel you have to doggedly pursue these puerile internet warz non-points. You have even (finally) conceded yourself that the pattern is the same. And Wander, Ico, and Emon are the only ones in any of the games with this pattern. None of the other guards, the queen, yorda, mono, colossi, architecture, etc. have the same pattern.
I like jett's idea that it is some sort of religious or priestly garb. Emon's is more ornate, befitting his role. Maybe Ico was some sort of acolyte? This begs the question of why would Ico be suddenly brougt then, and not as a child? It should be obvious that he has horns. Well in the game it appears that he is wearing bandages around them, so it seems possible that they grew recently, as opposed to being born with them as the child in SotC is.
In addition to the literal meaning of the tabard, it's interesting to contemplate the symbolic meaning. Concerning just Wander and Emon, you could say that they are equal and opposite, as duality is a big theme in both of the games. Emon represents order and light, Wander perhaps chaos and darkness. The relation to Ico is more abstract perhaps. Both Emon and Ico did vanquish a demon, so maybe in this way they are both "light", but Ico seems to have brought chaos, instead of fulfilling the twisted "order" of the queens castle and its rows of caskets.