Because of what I do/what I told her during my brief rotations on Peds Neuro, when we had our little guy my wife would send me constant videos of his movements asking if it was infantile spasms.
We would get 2-3 ED consults a week for infantile spasms when I was on Peds. It is super rare - but def happens. But in general the poor kiddos all had morphological features that were suggestive of congenital abnormalities - none of the little ones who looked healthy ever were diagnosed with infantile spasms.
Sandifer’s was way way common.