One of the first things I told my natural mom and family after I met them was that I had this fear. Last thing I wanted was to go to a big family celebration and end up bolting in terror. And nmom told me that my memere had the same phobia, for as long as she could remember, and she was very uncomfortable with them. I found out that memere had tried and failed with therapy to fix it as well. In that moment, I didn't feel so terribly alone anymore.
Just like the balloons, the women in the family all seem to have issues with mirrors after dark, and close spaces. Just one of those curious things about family I suppose. The mysteries of how we all come to be, and fit together, even the quirky not so fun parts.