Larry...yes please listen to the other posters here and get that in writing.....so there will be nothing to stop you from getting your kids back.
You have been through a lot...and you will be able to get through this..always remember you are doing it for your kids....never forget how much they mean to you, and that you are their dad and they need you whether they are with their aunt or with you.
Stay strong for them Larry...
Good luck...and keep us posted...ps the grandparents are pissheads...