Crown Prince / Crown Princess

This term is used for the eldest child who is first-in-line to a throne and is expected to succeed, barring any unforeseen future event preventing this.
  The children of a Crown Prince or Princess are referred as Prince or Princess, the eldest inheriting their title-holder parent's title once they are crowned ruler; in that aspect, the title is hereditary. There can only be one Crown Prince or Princess in a kingdom.
  The heir to the title of King or Queen is typically referred with this title while other children are called Prince or Princess, sometimes with a number if there are many children, such as 'Second Prince' or 'Third Princess', 'First Prince' and 'First Princess' only being used as an alternative title for the Crown heir.
Type
Royalty, Hereditary
Status
In use
Form of Address
His Royal Highness / Her Royal Highness ; then Sir / Ma'am
Alternative Naming
First Prince / First Princess
Current Holders
Past Holders
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