Abused kid goes on adventure in Faerie, wants to stay. Should she be allowed to?

Sure, and within the confines of the story as it’s told, that’s pretty fair and standard. It’s just strange and amusing that this standard that’s completely the norm in fiction would be really, really weird in real life, sometimes unthinkable. Take the first Harry Potter book, it’s totally acceptable and normal to send Harry off to an extradimensional school on the say so of a weird giant and some letters, a place that his guardians have never seen or visited and can’t actually contact even in an emergency, and say “seems legit.” What if Harry gets molested there? Who can they even report it to? Can they contact Hogwarts? If they can and Hogwarts administration says “we’ll look into it” and never does, what do they do? They can’t even really contact this school they’ve sent him to, can they figure out how to notify the Wizard SVU? It’s almost curmudgeonly to point out that that adults let children routinely get into insanely dangerous adventures in literature, but sometimes I wish for some sort of curmudgeonly Sam Vimes character in one of these stories to stand up and say “What? No, I’m not letting a child do that! Are you insane?”

Missed this: it happens often enough to make your heart sing and keep you moving forward in a sometimes ugly world. It’s not happily ever after, but it’s a happy beginning and it definitely, definitely happens.

Emma isn’t going to be any worse off if she stays and is adopted.

If there’s any type of counseling in Pangea, I’d still have her and her adoptive mom lined up for at least a session or two. It sounds like an ideal pairing, but hopefully Emma’s new mom won’t expect her to be the child she lost.

If you send Emma back to our Earth she’ll surely talk about where she’s been and what she has been doing. Everyone will think she’s crazy, she’ll end up drugged to her little eyeballs, and eventually the abusive mother will get her back anyway.

The wings are clearly a badge of office. I thought the Athena picture made that obvious.

That’s not the assumption I had in mind. I was thinking of a situation more like that in Lewis’ Magician’s Nephew–that some early, human wizard was experimenting with travel between worlds, and that “you” and Emma got sucked in accidentally (or suckered in on purpose) into making the jump.

I think that’s part of what attracts people to many stories in the first place. The real world is just so much more complicated and uncertain that it’s nice to have a little artificial simplicity.

As for your second post: I do agree that there can be happy outcomes. I also think even a relatively unhappy foster living situation is still better than the original abusers. But the truth is often not going to compete with the fantasy options in the OP.

I dated a girl in high school who’d been abused by multiple family members, then was abused by a foster parent she was placed with. In high school, she was living in a group foster home with six other girls who’d all had similarly unsuccessful results (though for some of these girls, it was their behavior that screwed up earlier placement rather than the fault of the foster parents). Anyway, it was a step up from their original families, but only by a little.