I'm not a mental health expert, but I'd think in "our" world, it would have taken years of psychiatric help (including talking to a psychiatrist and a regiment of medicine) to help Lizzie. No matter how stocked Terminus is, I doubt they'd have those resources. Let's say, for argument's sake, they did have a psychiatrist. Would s/he have brought psychiatric medicine along? And in a quantity enough to see someone go for the full range of the treatment? And would it still be good for years or would it be past its expiration date. And what do you do with a Lizzie? My guess, in "our" world, especially after she killed, would be to isolate her. Where do you do that (assuming Terminus is a town like Woodbury, would they have a psychiatric hospital within its limits?)? And do you really want to isolate someone in a world where, at any moment, a herd of walkers could descend, causing you to flee in a hurry? That's assuming you tell them in Terminus about Lizzie. It doesn't seem good practice to me to go to a sanctuary, one of the few you're aware of, and say, "Hey, while we have two able bodied adults willing to help out, we also have an infant and a troubled child who has killed before and will most likely kill again." If I were in charge of Terminus, I might let the baby in, for survival of the species, but I wouldn't risk Lizzie. So, they don't tell them about Lizzie. In my opinion, that would make them accomplishes when she kills again. Or lures walkers to their gates/doors/whatever they have to barricade themselves from the walkers. And, then, when they meet the others from the prison who will ask about Mika (unless, they are so jaded, they just accept that her absence means she died and don't even bother asking about how she died), how will they answer? In "our" world, I don't think killing a child is justified, ever. In the world of The Walking Dead, well, "Needs must..." That does make sense. It's her way of coping with the world she's now in. In "our" world, she might have reacted by trying, unsuccessfully to kill herself. One of the (sadly) many people who use a suicide attempt as a cry for help. I have a feeling that if she really wanted the walker to bite her, she would have let it. I just mean I think there's story potential there, that won't be addressed on the show. Was Mika unaffected by these things or did she use innocence as her coping mechanism? My own personal "head canon" is that Lizzie saw her mother turn and wanted to understand it/believe that she wasn't gone, just temporarily transformed, with the hope that, eventually she'll come back. As things went on, Lizzie decided that the only way to be with her mother again was to be turned into a walker, but every time she came close, her doubt/sanity prevented her. But, her curiosity won out, and she decided she wanted to see what would happen to her sister, as a proxy for the (presumably, long gone) mother. Perhaps, seeing it happen to Mika would have given her the courage she felt she needed to allow herself to be turned. Or maybe she was hoping Mika turning wouldn't give her the choice to pull away anymore. To me, the true mark of a good story (book, show, movie, etc.) is that it allows me to think about it and create my own explanations for things. So, I am curious about these things, as it allows me to understand the show on my own terms.