I read spoiler but I don't know the whole story.
Just that the the old duchess really couldn't be pregnant, and when she got chased, well she discovered that she was pregnant but it was too late ?? She gave birth to a dead child and made a pact with a demon, so the demon possessed the child and go for vengeance
I read this somewhere before, so the grandfather was the one who spread the rumors about the duke's 1st wife ( cosette's mother) being barren so that she'll be cast away, because the grandfather wants his daughter (the Fl's mother) to marry the duke
I don’t really remember much but I think this is a spoiler
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So the blond sister is a demon so that’s why she was able to “call on the spirit” but I don’t know about the grandfather thing
Can someone spoil and tell me if the grandfather is hiding the existence of the blond “sister” from the start?? And why she was able to call on the spirit??