Mail a letter to her old address; it will get there, and it should get forwarded. Pray over it before you send it and leave it in God's hands with His Mercy and Grace upon it. Lord, speak favor over this situation and open her daughter-in-law's heart and mind to do what is right.
Explain how you miss her and that you can see the faults in your son (that's your biggest issue, her wanting to hurt your son). Tell her you understand why it's all happening and you don't want to get involved in it all; no sides. It's between her and him. She is going to think you will tell him things. Don't; give your word and stick to it, or she will take her away, and there will be no hope if she is on the "evil" side. Let them work it out together. Tell your son that in the beginning, grandparents do not have many rights, especially if they were not married. Ask before you do anything with your granddaughter. Let her know your plans and such. Keep her involved in your plans. It will be a matter of time that she trusts you. I pray that the Lord open her heart to let you in. You have nothing to lose. See what happens. Lord, have Your way in Jesus' name.
God bless you.
