grandparent wanting custody of grandchild in TN

I have a grandson who is the tender age of 2 1/2 yrs old. His mother and father have a joint parenting plan agreement that neither one tends to follow. MY grandson is passed around from house to house. He is begining to show emotional disdain. His mother only wants him when it is convenient for her. Usually between boyfriends and partying. His father only wants him to try and to control the child's mother. The baby's father works until after 9:00pm every night and leaves the baby with the girlfriend of the month.
As a stable grandmother, is there anything legally I can do to provide a stable and loving environment for him?

You can do this one of two ways:

1. If the parents will agree to it, you can get a guardianship or do an adoption.

2. If they don't agree with it, then the only way you're going to end up with a guardianship or adoption is for the state to intervene and take the kids from both parents. Then the state will look for a suitable home (usually relatives get first dibs).

In other words, you cannot successfully fight for custody of the child unless the parents either agree to it or are proven unfit.