Mich. Comp. Laws § 319.104: Fiduciaries; right to prosecute and defend suits; parties.

Sec. 4.

Executors, administrators and administrators with will annexed, receivers and trustees, may institute or defend such suits on behalf of their respective estates and trusts and the heirs, devisees, legatees, successors and assigns thereof. Infants and persons under legal disability may institute or defend suits by guardian or next of friend. Every person, including wives of owners, having any interest in such lands, whether in possession or otherwise, who is not a party plaintiff, shall be made a party defendant to such suit. In case of persons interested in such lands whose names are unknown, the bill of complaint shall so state, and such persons may be made parties to such suits by the name and description of "unknown owners."