It didn't matter if a prince or princess was ugly or sickly or
the village idiot; as long as they were of
royal blood, uncontaminated with that of commoners, that was all that mattered.
Carlos II of Spain is a case point for that problem; in delicate health, retarded,
impotent, and terribly ugly, Carlos was the end result of generations of inbreeding among the Spanish Habsburgs.
She was a sickly little girl; her nose was always running and she coughed a lot.