Christmas parties at my grandparents house usually meant spending the entire day in the basement because there were too many people. For me It’s usually not a number of people thing, but how many people are in a room relative to its size.
I do want to give you some good news though. Despite my persistent anxiety, I have recently discovered that it has made me incredibly resilient to sudden stressors I wasn’t anxious of prior. I would not be surprised if your daughter builds the same resilience either. It won’t be easy, nor intentional, but it is a small gift from it.