S.C. Code § 44-13-20
Any individual, legally a resident of this State, ordered to be admitted to any mental health facility under the laws of any other state, may be admitted, upon satisfactory proof of residence, to care and treatment in any State mental health facility of this State. The orders of any court of competent jurisdiction of another state or of the District of Columbia authorizing admittance of such individual to a mental health facility shall have the same force and effect upon his transfer to this State as a lawful order of any court of competent jurisdiction in this State. A certified copy of such order shall be furnished the Department of Mental Health prior to the issuance by the Department of Mental Health of any authorization of transfer of such patient. Jurisdiction in all further matters relating to such mentally ill person shall vest in the judge of probate of the county in which the mental health facility, to which such person is admitted, is located, during his confinement therein, or the judge of probate of the county in which he is legally resident.
S.C. Code § 44-13-20