I’ll go with the low-hanging fruit: Mein Kampf. I’ve read it, cover to cover. As a piece of propaganda, it’s good. As an example of good writing? Absolutely not (though I will admit I have only read it in translation). Oh, and the whole fascist, racist, and generally shitty worldview of the author that he infuses into the text. And the fact that the author is literally Hitler. You 5-star that book? You’re a Nazi. Period. And as a Jewish person, I don’t look too kindly on them.
Thumbs up to your stepmom! Children are often interested in banned books. Some can be good some not.
If a child is already interested in a banned book, trying to forcibly take it away isn’t a good way to convince them the ideas in it are wrong.