Fiduciary law is an ancient legal device to protect the interests of relatively powerless persons:

“Courts of equity have carefully refrained from defining the particular instances of fiduciary relations in such a manner that other and perhaps new cases might be excluded. It is settled by an overwhelming weight of authority that the principle extends to every possible case in which a fiduciary relation exists as a fact, in which there is confidence reposed on one side and the resulting superiority and influence on the other. The relation and the duties involved in it need not be legal. It may be moral, social, domestic, or merely personal.” [Beach v. Wilton, 91 N.E. 492, 495 (Ill. 1910).]