Sure. I mean you'd only have to ignore
everything about their characters
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Amber being motherly does not = her being related to MC. I would think that she'd know whether or not she had a nephew in the same age group as Bella. It's probably just her maternal instincts kicking in seeing as MC's young enough to be her son... because... you know... that happens. Furthermore, they look nothing alike. Outside of the color of their eyes, what do they physically have in common? Having the same eye color(vaguely) does not automatically make them related. Lol, do you think that everyone with blue eyes is of relation? While we're at it, we'd better make sure that Sasha and Nadia aren't related. Because... you know... they're both blonde with blue eyes. Unlike your theory of MC being related to the von Halens, Nadia and Sasha are both slav names(russian), so right off the bat, they have a lot more in commonღ
P.S: This is for anyone that took it seriously and actually thought "Omg... maybe they ARE related!"
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P.S#2: I really
could care less about someone else's interests, but I've seen many users trying to find relation between characters on these forums like they
have to be related. Why can't they be normal people that are attracted to one another or fall in love with one another? Why must incest be inserted in there somewhere? Again, not attacking anyone that's into that sort of thing, but why look for it somewhere that it obviously isn't? I can already
feel the heat that this comment is going to get lol
Edit: Also, Bella's little sister had blue eyes, so that kinda throws that whole theory out of the window♡