S.C. Code § 32-11-20
If any note or bill, whether filled up before or after having been signed or endorsed, shall be negotiated or transferred after the death of such drawer or endorser by an agent duly constituted in the lifetime of such drawer or endorser, such note or bill shall be valid and binding on the estate, in like manner as though he had not died before such negotiation or transfer, if the receiver of such note or bill received the same bona fide, without a knowledge of such death, and if the act of the agent would have been binding on the principal if it had been done before such death. The act to be done, either under the power of attorney or authority or in relation to the bill or note, must be done within nine months after the death of the principal or of the drawer or endorser of such note or bill.
S.C. Code § 32-11-20