Red coat, brown coat. SPOILERS!!!
Near the end Harbours expresses that he wishes that he had the Red Coat instead of the Brown one. If I remember correctly the brown coat was bought for Wilbur. This is also when Harbour talks about how when their dad was on his deathbed, he mistook Harbour for Wilbur and that for that moment he became Wilbur.
There seems to be a whole theme where Harbour becomes Wilbur and Wilbur becomes Harbour. This shows towards the end when Mary brings Wilbur a decoration and he says that Harbour was into those things but when Harbour comes out home he clearly says that Wilbur made it. Wilbur during his rant sequence on Christmas complains about how Harbour is the only one who knows how to Roast the Duck, and do all the responsible things around the house. He knows at this point that he has to become Harbour and let Harbour become him (the one destined to die).