A Hereditary Monarchy is a form of Monarchy in which the Monarch is appointed autocratically by Peers of the Realm or a Royal Council of some type, according to the successor's ancestry. In Hereditary Monarchies, the first-born child (usually the first-born son) of a reigning Monarch becomes the successor of that Monarchy by law, regardless of the Monarch's personal preference. If the Monarch has no children to succeed them then the Crown will pass onto their closest blood relation, or possibly their consort in some instances. In the event that there is no potential successor for the Monarch, it is common for them to appoint a successor or for a foreign power to claim the throne of the Kingdom or Principality.