10/16 diamonds in the shadow

I can infer that Alake was either disabled or very scared and didn't want to talk. She might be scared because of the 5'th refugee that is following them, or it could be because all of the violence scarred her and she doesn't want to talk. I think before the end of the book she will talk or overcome her fear. If she doesn't then she maybe able to talk to people with sign language or a code.