Fils de France (, "Son of France") was a title used by children of the reigning King of France. It entitled the holder of the title to the style of "Royal Highness". However, that was rarely used. The French court preferred to use terms such as "Madame" and "Monsieur". The reigning king, his wife and their children were collectively referred to as the "Famille de France" ("Family of France"). The grandchildren of the king were entitled to the rank of "Grandson or Granddaughter of France". But the more senior of the two titles was that of "Child of France" due to being a child of a monarch. In French a "Child of France" was a "Fils de France". 