Regent
governing official in the absence or incapacity of a monarch From Wikipedia, the free encyclopedia
A regent is a position of government in a country where there is a monarchy (like a king or queen). As an "acting monarch" the regent does the job of a monarch where the real monarch is either too young, sick or cannot do what they are meant to for some other reason.

A regent may also be voted in if there are no heirs in line to the throne, for instance, if the current monarch dies with no surviving relatives.
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