Q: Son does not want to go back to other parent

A: If the other parent is the custodial parent you have a duty to return the child to them when your parenting time as stated in your parenting plan is done. You don't let the child decide, you put them in the car and drive them home. The other parent doesn't need to mediate with their own child, that's ridiculous. You don't put a child in a position of power to have rights to decide custody or parenting time or to negotiate terms. That will just unleash more problems once the child is taught they have power to play their parents.

You can be charged with custodial interference if you assist your child in not going home. If you can't get the child in the car to drive them home, then call the other parent and tell them to drive over to your house and you will put the child in their car.

Not knowing the age of the child it is hard to say what other plan you can try if the you can't get the child home to the custodial parent. You and the other parent are going to have to get creative. I am very reluctant to suggest that you get children's services involved but that may end up being your third option and I don't know if they will do anything. But throwing your child out of your house might get you in trouble for child endangerment. You are going to need to make an appointment to speak to an attorney if all else fails.

Now if there is a real concern about the other parent's ability to parent your child, then you have to go back to court and file for custody. Can't really say if this is a good idea because I don't know the facts of your situation. Speak to an Attorney.