I don't know where you live, but there are all kinds of services available through FIA and WIC for pregnant women. She has more than a homelessness problem, whe is likely into some kind of addiction and unwillilng to deal with it. There are a lot of services particularly for pregnant and homeless people, she is not using the social system. My sister is a social worker so I know what is up with this. SHe may have wmental health issues as well and be unwilling to take advantage of the help available, but is she is truly pregnant they would find a place for her to live today.