@conscript117 - Once more you start a post with some absurd strawman that was never relevant to begin with. In fact, if you had been paying attention you'd once again find it's already something I've touched upon earlier.
Then you immediately hop back to the same old spiel. Yes, I know children are hyperactive and mischievous. I keep telling you this, but you're still entirely missing the point. For some reason, you seem completely incapable of separating the observed normal behavior of a physically, and mentally, healthy child, with the observed behavior of a child that has undergone intense physical, and mental, abuse. These twins belong at the extreme end of the latter. To put it as plainly as I can for you: they are not normal fucking kids! Even if they were completely oblivious to the cause (which they are not), it would still be highly irregular for them to act this way given the events they've been through. Getting a slap on the wrist as discipline for spontaneously sneaking a cookie would never leave the same impression as getting your face and body smashed in, and then starved.
Even normal, healthy children, are extra sensitive when matters of fear are involved. If they're told a monster story, they may develop a fear of the dark. Even if it's not entirely rational. Now take two children, who have a horribly abused past, and have lived a monster story, and they know monsters are real, and tell them they're everywhere, and it's not safe outside. They're not going to skip off to town alone.
If you genuinely believe that the author portrayed the behavior of the twins correctly, even with the insight we have as readers observing their past, then you'd have to be either completely insane, or utterly ignorant to the amount of damage that abuse at the level they received has on a person -- especially the young.
If you don't feel like re-reading as a refresher of what they've gone through you can simply read the comments by
@cor3zone or
@Raikuha to hopefully get a better understanding. From a character perspective, their behavior still makes little sense.