Grandparents seeking custody

I need to know my rights to file for custody of my special needs grandchild (3 years old). She has a dead beat dad who has never supported her financially or otherwise. Her mother is bi-polar and has never been hands on. She has never been left to care for her overnight by her self. I have taken full care of her since the day she came home from the hospital. Her mother lived here initially although she was very unstable mentally while she was here. She moved out and married someone about 6 months ago they both quit their jobs are getting evicted. She visits for a couple of hours once or twice a week and is threatening to take her and move out of state. I have been told by an attorney that the only way I can file for custody is if a biological parent does first. She requires substantial care as she has multiple medical conditions. Please Help Me!

Generally speaking, grandparents can only file an action for visitation if there is an ongoing custody dispute. However, you can institute a custody action based on the parents neglecting the child. We have an article that talks about this in greater detail: Grandparents and Custody.