
"Did I kill YOUR parents?"
Oh thank goodness they're not actually related!
"They were OUR parents"
(⊙…⊙ )

I'm pretty sure they are related because the brother said " just because they birthed us doesn't make them parents". The younger brother isn't claiming them as his parents because of how the were treated. Sounds like it's likely they insisted that the kids were insane because of the things that they could see.
Thank you uploader-san (づ ̄ ³ ̄)づ
ALSO FUCK THAT OLD MAN PIECE OF SHIT I'LL FUCKING KILL YOU!!!