You accused a creator of "cashing in" on his sister's death, and you feel insulted because someone called you out on how tasteless and unfeeling such an accusation is? If you had just said "I don't think I should have to temper my judgment of a work just because a character was based on the author's dead sister," fine. That's a perfectly valid opinion to have. But to flat out accuse Johns of exploiting his sister's death for financial gain is completely uncalled for.