Welcome and I'm sorry for your situation.
It might be a good idea for you to talk to a lawyer to learn what your rights are and to find out what you can do to ensure that your grandson is safe.
Also, for support for yourself, you might check out AlAnon in your city.
We have a Forum for Friends & Families which could be helpful as well:
https://www.soberrecovery.com/forums...ly-alcoholics/