D.:
I'm truly sorry you are going through so many problems...
You need to find a lawyer to help you navigate this messy business of child custody and divorce...
If HIS parents own the house and you are renting it from them - they may ask you to leave - grandchild or no. I do not know the rental laws in Nebraska nor do I know the custody laws...you need have a lawyer involved so that your rights are protected...unfortunately, you have learned you cannot trust your husband to tell you the truth...he is already trying to screw you over (as noted in your previous post).
DO NOT SIGN ANYTHING without having a lawyer check it over for you and ensure that you are being protected.
You said the other day you stated you were on the list for public housing/section 8 - DO NOT REMOVE YOUR NAME FROM THIS LIST!!!!
Go to a W.'s shelter and they will direct you to a lawyer that can help you - they will also direct you to other help you may qualify for. Keep in mind this is NOT a permanent way of life - this is a HELPING HAND and TEMPORARY measure. Find out what classes you will qualify for for an education, certification, etc. so that you can get back on your feet and on your own.
Once you get a lawyer - you will be able to fight (ugly word but that's what you are doing) for custody of your son. You will need to document EVERYTHING...if he hits you or your son, file police charges. If he says demeaning things (calling you or your son stupid, worthless, etc.) if he has hit you then you need to file a restraining order against him. Again - do not SIGN ANYTHING he has given you....DO NOT SIGN ANYTHING that he has given you from his lawyer...PERIOD....GET A LAWYER NOW!!!
Good luck