I am seriously not concerned about the situation

. I am not upset that people know my kids aren't vaxed. It's information that I share freely when asked. Every once in a while, someone actually listens to the reasons! I wrote this post simply because I couldn't believe people were reacting the way they did! I'm not upset about it, not worried about it, not guilty, not sad or mad. Just rather astonished

. I am going to the wedding and I'm going to have a good time. I am not concerned about ulterior motives, or who is trying to accomplish what. I don't waste my time or energy wondering if other people are playing passive-aggressive games. I spent an eternity doing that with my mother, and I won't do it anymore. It's my brother's wedding, we are in the wedding party, we are going, we will have fun (barring exhausted, cranky children

). If people aren't happy with it, that's their choice

. As pps have pointed out, sil is the one who is suffering as a result of what she has done, not me. I suspect this turn of events was quite a surprise to her, and not at all what she intended whenever it was she shared this information about me with others.
I do not intend to confront sil about what she has done. She is young, immature, and may have some emotional issues as well (she reminds me a little of my mother). I know from experience that it's futile to have healthy, functional conversations with people like this. I know from experience that explaining to her she has violated a boundary, and would she please not do it again is useless. So I won't waste my time.
What I
will do, however, is take more steps to protect me and my family in the future. This specific situation is only a symptom of a larger issue, which is the overall relationship between me and her. I cannot control what she does or says. The only thing I
can control is what I share with her. I was already somewhat guarded around her, but she has clearly demonstrated that she is not to be trusted so you better believe I will be even more careful now. I am glad to have learned this lesson so early and in such a harmless manner

.