I want to get custody of my niece,her mother passed away a year ago.my brother is unfit.he has no job,bounces from house to house and has a drug problem.what can I do?

How did your brother get court appointed custody ( or guardianship )

Where is the bio father of the child, since he would have first right to custody.

But you file in court for custody of the child, perhaps you can get brother to sign custody over