Lice Puppies
Lice were a near-constant issue for the palaces, but not enough to stop King Charles II. The royal highness of England frequently permitted his lice-infested puppies to sleep with him in his bedroom, and typically also in his bed. In his mind, dogs weren't able to give him lice for some reason...
King Stinky
Of all the royals, King James I was said to have been the nastiest in terms of hygiene. He never bathed once in his entire life. As a result, his lice infestation was one of the worst in history. It's said that later in his life, he agreed that maybe he should have been a little cleaner...