Grandparents Raising Children Support Group
This community is dedicated to grandparents who are the primary caregivers of their grandchildren. In cases where the parents are not willing or able to provide adequate care for their children, grandparents may take on the role of primary caregivers. Join the support group to find support, share your experience, and get advice from other members.
I think you would have a great chance at gaining full custody of her as it sounds like the bio's are unstable and into drugs/alcohol.
I think I would leave things alone as they are.
Perhaps consult a GOOD attorney who knows a LOT about ALTERNATE FAMILY Custody - not just divorce custody. They are NOT the same. EVen if they tell you they are or that they know. I have been to three different local lawyers who said they knew what they were talking about who would have taken the exact WRONG route had I retained them. Be very careful what lawyer you get advice from. Try to find one that deals specifically with alternate families. They DO exist. If there's one in WI, there's one most anywhere....lol.
Wishing you the best!