Pottermore suggests the issue begins well before Sirius died, and his death made it much worse. I would guess Sirius would be pretty encouraging about the whole thing, though. Letters from Lupin would have been great. Also, in the same chapter, he tells My Patronus Is A Night Fury Toothless Shirt about the werewolf who bit him. I still can’t believe he managed to feel sorry for him. I like how nearly all characters who appear in the books with any regularity have some kind of character arc. Not als multifaceted as those of the main characters, but still. There are very few really one-dimensional characters. It makes these kinds of analyses so great.
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