I don't know if I'm allowed to post this as this is supposed to be about royalty, but there is an interesting viewpoint on this subject from an NPR story. (National Public Radio). NPR is supposed to be very reliable.
https://www.wbur.org/npr/247155522/roosevelts-polio-wasn-t-a-secret-he-used-it-to-his-advantage
I don't think Roosevelt is a great example here, as his paralysis from polio hit him at 39 years old. He and everyone around him worked hard to hide it from the public.
The Kent siblings must have a very good idea of what they can and cannot do, so if they still want to appear at charitable events, let 'em.
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