I want to look into getting custody of my 3 year old niece. My sister is a drug addict and has not be taking care of her properly for a long time. I took my niece from her because she is doing drugs in front of her. I am assuming that you could say I have her illeagly. I mean my sister knows she is with me but just doesn't care. Her father comes in and out of the picture. Her has done many different drugs as well and I have no idea if he still does. But I do know that he has no job and has never paid any child support and goes from place to place to sleep at different family houses. SO my question how do I go about trying to get custody or her. Can my sister sign something that says she gives me custody? Do we have to go in front of a jodge or can we just do this with a lawyer?
If I have temporary custody can I apply for family assistance?

Any help or suggestions anything will be helpful not to sure where to go with this.

First off you could be appointed guardian of the child and later pettion the courts for custody using the grounds you have stated. That way it shows that your trying to follow the law and also trying to look after the best interests of the child. Are you married ? If so would your husband be willing to adopt ? As far as the family assistance goes you need to call your local office and ask what form of custody they would need in case you have to apply for it.
It can vary from state to state.