That's a symptom of overfitting, which requires the image to be repeated in the training hundreds or even thousands of times. That generally only happened in earlier image generation models, more "modern" ones ("modern" in this case being measured in months because this is such a fast-developing technology) have much better curation of their training sets to avoid exactly that sort of thing. Nobody wants AI image generators that replicate images from their training sets, what would be the point?

So if you want to find an image model that gives you a close duplicate of an existing image of child abuse, you'll need to find one that was sloppily trained with a training set that included hundreds of duplicates of child abuse imagery. I kind of doubt you'll be able to find one of those.