South carolina constitution
Article IV: executive department
Section 12

Thereafter, if the Governor transmits to the President of the Senate and the Speaker of the House of Representatives his written declaration that no such inability exists he shall forthwith resume the powers and duties of his office unless a majority of the above members or of such other body, whichever the case may be, transmits within four days to the President of the Senate and the Speaker of the House of Representatives their written declaration that the Governor is unable to discharge the powers and duties of his office. Thereupon, the General Assembly shall forthwith consider and decide the issue, and if not in session it shall assemble within forty-eight hours for the sole purpose of deciding such issue. If the General Assembly, within twenty-one days, excluding Sundays, after the first day it meets to decide the issue, determines by two-thirds vote of each House that the Governor is unable to discharge the powers and duties of his office, the Lieutenant Governor shall continue to discharge the same as acting Governor; otherwise, the Governor shall resume the powers and duties of his office.