I find this hard because I often feel like children are super idealized in media and it looks like the people who write them have never really interacted with children and seen how rude, weird, and random they all actually are, not to mention emotionally unstable and trigger-happy.

I mean, I liked Nanako fine, but she was still kind of too perfect, being nice to everyone, and doing the frickin' laundry at age six. She's still probably one of the best portrayals of a kid in Japanese popular media.