It was the only change in their day-to-day life (they, and myself, are both housebound due to disabilities), and is a known risk of any injection, afaik. I’m not into the med field myself so this is all secondary knowledge, but I found the name of the condition: https://en.wikipedia.org/wiki/Guillain–Barré_syndrome (jeez that’s a mangled url).

Doubt all you want, but I watched it unfold over the course of a week before they were admitted to the hospital, and stayed there for over a month before being able to return home. I watched the difficulties grow, and I went to see them in the hospital a couple weeks after being admitted. It was absolutely heartbreaking. They already had enough to deal with before it occurred (physical and cognitive impairments, from birth) and it was just… just really trying, showing strength and being positive while scared I was going to lose a sibling.

E: paragraph two, “Sometimes this immune dysfunction is triggered by an infection or, less commonly, by surgery, and by vaccination.”