There is public housing for married folks with children and also single, chilldless people; you may have to call around. Each city and suburb usuallly haa a "housing authority," spending federal funds.
But the wait takes forever. This is "better" assistance than food stamps; dollar for dollar, you get more.
Homeless families with minor children in shelters get priority; also, people who are currently living in hazardous, unsafe housing.
If a family is living with another family and it's a tense situation, the best thing for the family might be swallow its pride and go to a homeless shelter.