The first has a bit of truth but they adjust like we do to familiar smells although per senting isn't really possible if the rodents are in the same room the rest is 100% myths. You will find in general that there are almost as many myths as fact when it comes to royals double check every statement and get some reputable books to back up what you read. I like Philippe de Vosjoli and D&T Barker both have very good books. The Barkers in particular is very very full and is well researched and cited. They can help separate fact from fiction. Remember that in the early days the knowledge of royals was very poor and loose some of the myths were 'fact' 30 years ago.