Optimist4ever57: Hello!
I am not a grandparent and cannot speak from that experience; but I am a mom of two adult children, and I joined this site about 10 years ago when I was at my wit's end (my son was nearing 18, failing school, participating in risky behaviors, breaking the law, substance using on a regular basis and trying to take advantage of mom and dad and to manipulate to his advantage).
"We tried" as parents; and hopefully and it looks like some of what he was taught and experienced that was positive has stuck. However and unfortunately, at that time 10 years ago and numerous years before, by throwing help, enabling, bargaining, pleading, living in fear, and trying to fix things for him -- well it came to a dead end. I had to face it and he had to face it that he was responsible for himself, was becoming an adult, and needed to be accountable.
It was hard for me to let go and let God but it was necessary.
My son did move out of our house about seven years ago, has been working hard and, yes, struggling; but, he has been living independently since then and, at this point in time, is running a successful business.
All these years later and with experience and loads of support from this site and otherwise, I know I can "be there for him" but "cannot fix it for him."
Each person's experience is different, I know. I am sharing just to give one mom's experience and what worked for me.
Making and keeping boundaries (it takes time and practice, practice, practice for me) has made a huge difference. Not only in my relationship with my son but with others, who I encounter on a daily basis and where there is the potential for toxicity and unnecessary drama.
Hoping for all the best for you and your family. Let us know how it goes. Hugs