With all due respect, I am very fortunate that the Lord does not share the same parenting tactics for His children.
I spent many years ignoring Him and doing things that I know He did not approve of, yet when I, the prodigal child, finally came home, He took me in His arms! He has since then helped me to sort through the ashes to find the beauty. It wasn't for nothing. It all had purpose. AWESOME, He is AWESOME!!
I understand the temptation of giving back what you get, but sometimes you have to practice giving the same grace you have been given, even if it is not from the person you have to extend it to. How else will they find out what it is and what it means? It is difficult. I was always an "eye-for-an-eye" type person before I became a Christian. Old habits die hard.
Looking forward to more responses to my questions. Thanks so much for the ones I have so far! Sorry to hear that time has been missed with your grandchild and son. I will be praying for healing and acceptance in your situation. And freedom for them as well!