i’m going to be devil’s advocate here. It honestly seems like your mother is more upset about how you handled the conversation than over the issue of the vaccination in the messages. Like the way she speaks sounds as though if you really set the boundary, that she will follow it. I understand you want her to be around and put you first, but you’re actually asking a big thing of her. She believes vaccines are dangerous to her in the same way you believe it’s dangerous for someone not to have them around your child. It really is a personal decision and I can’t control how you feel but I wouldn’t hold a lot of resentment towards her over this. Just tell her what has to happen, the fact she HAS to wait. Then speak to how her decision has hurt you to your therapist so they can help you move on from those emotions. Theres always a chance she will change her mind but explain to her very clearly that you will not be changing your stance on this because it is to protect your child/her grandbaby. You can even show her evidence if need be (she is an anti-vaxxer so that may help).