((Newengland))
Welcome to SR, but I'm sorry for the reason you are here.
I am a recovering crack addict, and I highly doubt she is going to pass the hair follicle test. If she does, children's services will be watching her closely.
I had to hit bottom before I got into recovery. I had no one pay for a hotel room, and I was homeless. I lived that way for over a year. I am also a huge codie (codependent) and wanted to solve everyone's problems. I had to leave my XABF (ex addict boyfriend) because he was still doing crack.
As hard as it is, she is an adult and she needs to face consequences for her using. It's the only way most of us find our bottoms and realize the only way to go is up.
I'm glad the babies are being taken care of by people who love them. I know you love your daughter, but it's honestly time to let her find her own way.
Many people here have gotten a tremendous amount of support through al-anon or nar-anon. It will help you put your focus back on you and your granddaughter.
Whether or not you go to a meeting, the people on this forum are awesome and there are many who are raising grandchildren for the same reason, so you are not alone.
Hugs and prayers!
Amy