In the case of Charles, his O negative blood has been recorded. And been written about.
BUT… does it mean you have to be interested in him?
In case that there is any doubt:
In no way does my frequent reporting on Rh- individuals in the public eye indicate fandom.
I mention the “royals” because
a) many of you have shown interest at least due to their high Rh negativity
b) they happen to be Rh-s we all know. We all know different Rh- individuals we are around offline, but who else do we have in common?