Dystopian YA book- the two main characters had to take care of a child. She tries to teach the child her name by pronouncing it slowly. She also might have lived in a shipping container?

[Riley]

This is super vague so any help is appreciated. I remember two scenes, but they might be from two different books. Also, if it's helpful to anyone, it was a book from my school's Battle of the Books competition, if anyone knows where to find previous years' lists. It would have been in the 2016 or 2017 middle school competition.

The book was post-apocalyptic, and I don't remember there being many adults, if any.

The first scene I remember is of a young boy, the male MC, who is looking for the female MC. She lives in a shipping crate (I think she lived alone, or with an old man who moved out a long time ago, but I'm shaky on that part). If I remember correctly, she was in a neighborhood of sorts where everyone lived in shipping containers. (This scene might have also been reversed- maybe the boy lived in the shipping container).

The second scene I remember is both main characters are riding in some kind of cart with a child, and the girl MC tries to teach the child how to say her name by pronouncing it syllable by syllable. I remember the name was really feminine and not super common. It might have started with an A?

Like I said- super vague and possibly from two separate books. Any ideas are appreciated. Thanks!

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