Keep strong girl....I had a brother who was similar in disrupting my family growing up. If you have kids in the house it is not fair to them to have the burden of a drug using family member. Your sister-n-law could also attract trouble to your home. Having gone through this with a brother, I feel tough love is the only way. And yes, there might be Pathways or Uran Ministry who can help your homeless SNL and her child. It is so hard, but knowing that she is there for the taking should help you stay strong.