the authority of the attorney in fact under a power of attorney, whether durable or not, shall not terminate and the attorney in fact may continue to exercise the authority conferred, faithfully and in the best interests of the principal, until the principal returns or is publicly declared dead by a governmental agency, domestic or foreign, or is presumed dead because of continuous absence of five years as provided in section 472.290, RSMo 1986, or a similar law of the place of the last known domicile of the person whose absence is in question.
§ 404.714, RSMo