Odds and Ends
Australia DOES have a Royal Family. Despite being an soverig
23 4, 7:10pm
"Prince" was originally the title of a ruler. It still is in some countries. It is also a generic term for kings, emperors and suchlike. That is why Machiavelli's famous book is called The Prince. "Prince", in this sense, is "fyrste" in Danish, as in "fyrsten af Monaco".
A king of England got the bright idea to appoint his eldest son prince of Wales. This they have done ever since. The king of France, not to have his son outranked, appointed all his sons princes. From then on, "prince" has taken the secondary meaning of the son of a king. It is also used for consorts of queens regnant. My native Danish has imported this usage as "prins", as in "prins Christian".