Hi and welcome back !
Yes, we do have several families w/ multiple members with Chiari and related conditions...
I feel I have several family members with similar symptoms, but some were given a DX of fibro and they do not feel the need to look further....it is hard to explain that dx could be wrong....so until a new symptom crops up that does not fit under the fibro umbrella I have to wait and let them think they have a proper dx...and they may well have...but it is too coincidental.
I feel like I want my other family members to have the opportunity to know especially my children. I think it is better to know than have to struggle for so many years like most of us have in order to get a proper diagnosis. I will consider it a huge blessing if the never have a symptom but I still think that knowledge is power. I also have ADHD and two ladies wrote a book about being diagnosed with ADD/ADHD as adults with the title "You Mean I am Not Lazy, Stupid or Crazy". Thats how I felt about finally getting my Chiari diagnosed- I would get so frustrated when I would be made to feel like a hypochondriac when I would go to the doctor about my symptoms. I knew I wasnt one- I take care of my children everyday and I go to work everyday. Just feel like I want my other family members the relief I felt- that is why I pushed my sister to get checked because her problems have kept her from working like she needs to lus she is a single mom.
It is possible chiari runs in familys.i read about a family where the mother and all of her 3children had chiari and other cases.i am so sorry u and ur sister do have it.i am so glad my twin sister doesnt have it...it would freak me out knowing that anyone of my family has to go thru this.