Michigan Compiled Laws, Chapter 700. Estates and Protected Individuals Code § 700.7303

(a) A conservator, plenary guardian, or partial guardian having authority to act with respect to the trust may represent and bind the estate that the conservator, plenary guardian, or partial guardian controls.

(b) An agent under a durable power of attorney having authority to act with respect to the trust may represent and bind the principal if a conservator, plenary guardian, or partial guardian has not been appointed.

(c) A guardian having authority to act with respect to the trust may represent and bind the ward if a conservator of the ward's estate has not been appointed and no agent under a durable power has authority to act.

(d) A trustee may represent and bind the beneficiaries of the trust.

(e) A personal representative of a decedent's estate may represent and bind persons interested in the estate.

(f) A parent may represent and bind the parent's minor or unborn child if a conservator, plenary guardian, or partial guardian has not been appointed.