Detailed Answer

Short answer: Yes. Under Michigan law, heirs of a deceased co‑owner can and generally must be included in a partition action if they acquired legal title or an interest in the property when the co‑owner died. To add them, you identify who holds the decedent’s interest (heirs or a personal representative), then amend your complaint or move to join them and serve them according to court rules. If heirs are unknown or unlocatable, the court permits alternative service methods (publication) or appointment of a guardian ad litem.

How Michigan law treats a co‑owner’s death in a partition case

A partition action divides co‑owned real property among owners or orders sale and distribution of proceeds. Michigan statutes governing partition actions list who must be made parties to such suits; the court must be able to bind everyone who has an ownership interest. See the Michigan partition statute: MCL 600.3301.

If a co‑owner died before the partition case is filed (or before final resolution), that person’s interest passes to whoever inherits under the decedent’s will or under Michigan intestate succession rules. The potential owners are:

The personal representative (executor/administrator) of the decedent’s estate while probate is pending.
The decedent’s heirs or devisees (people who inherit by will or by intestacy) once title transfers or if probate is not opened.

Intestate succession and wills are governed by Michigan’s Estates code; see the intestacy provisions for how heirs are determined: MCL 700.2101 et seq.

Practical steps to include heirs in your partition action

Confirm whether the decedent’s estate is open in probate. Search probate records for the county where the decedent lived or where the property is located. If a personal representative has been appointed, you typically join that representative as a party because they represent the interests of heirs/creditors during probate.
Determine who the heirs or devisees are. Review the decedent’s will (if any) and the family information that determines heirs under Michigan law (spouse, children, parents, siblings, etc.). If no will exists, the heirs are those defined under Michigan’s intestacy rules (MCL 700.2101 et seq.).
File an amended complaint or motion to add parties. If you already filed your partition complaint, you can generally amend it to join additional necessary parties (the heirs or the personal representative). If you have not yet filed, name the heirs (or the personal representative) in the original complaint.
Serve the new parties properly. Serve heirs or the personal representative according to Michigan procedural rules. If a personal representative is named, serve them at the address shown in the probate appointment. For heirs, use personal service where possible. If heirs are minors, incapacitated, or unlocatable, special procedures apply (see below).
If heirs are unknown or cannot be located, ask the court for alternative service. After demonstrating due diligence in trying to locate them, you can request service by publication or other substituted service and ask the court to appoint a guardian ad litem for unknown or minor/unborn heirs. Courts allow these steps so the case can proceed while protecting the rights of absent parties.
Provide proof of title transfer or the estate representative’s authority. Attach a certified copy of the death certificate, letters of authority (from probate), a recorded deed, or affidavit of heirship to show who currently claims the interest.
Be ready for potential delays and costs. Adding parties, particularly unknown heirs or contested heirs, can extend the timeline and increase legal and court costs. The court must ensure due process for all parties before entering a final partition order.

Common scenarios and how to handle them

Probate pending with a personal representative: Join the personal representative to represent the decedent’s interest. The representative can defend or settle that interest on behalf of the estate.
No probate opened and heirs identified: Name the heirs directly in the complaint and serve them. If heirship is disputed, attaching an affidavit of heirship or other supporting documentation helps.
Heirs unknown or missing: Show the court you searched for heirs (probate search, records, last known addresses). Request publication service and ask the court to appoint a guardian ad litem to represent unknown or unborn heirs’ interests.
Minor or incapacitated heir: The court will require a guardian or conservator to represent those interests in the partition case.

What the court will expect you to show

The judge will want clear evidence that (1) you identified who owns or may own the decedent’s interest; (2) you have properly added or attempted to add those parties; and (3) you used appropriate service methods. Typical documents include a death certificate, letters of authority from probate, recorded deeds, affidavits of heirship, and proof of service or publication.

When to involve a lawyer

If heirs are many, hard to find, or contest ownership, or if the decedent’s title history is unclear, consult a Michigan real‑property or probate attorney. Complex disputes, claims against the estate, or multiple jurisdictions raise procedural and substantive issues that benefit from counsel.

Helpful Hints

Start with a title search and a statewide probate record search to see whether a will exists or a personal representative was appointed.
Obtain a certified copy of the decedent’s death certificate early. Courts often ask for it when you assert someone died.
If probate is pending, join the personal representative rather than each individual heir while the estate is open.
Keep a written log of your efforts to locate missing heirs (addresses tried, phone calls, searches); the court will want evidence if you later ask for service by publication.
When naming heirs, use full legal names and last known addresses; include minors and persons with unknown addresses as “unknown heirs” and ask the court for direction on service/representation.
If you must use publication, follow the local court’s publication rules strictly – mistakes can require re‑service and delay the case.
Collect and attach supporting documents (death certificate, letters of authority, deed, affidavits of heirship) when you file your motion to add parties or an amended complaint.
Consider mediation if heirs disagree about partition in kind vs. sale; mediation can cut costs and speed resolution.

Useful Michigan law references:

Partition statute: MCL 600.3301
Michigan intestacy / estates provisions (for identifying heirs): MCL 700.2101 et seq.
Michigan Courts main site (local court rules, forms, probate information): courts.michigan.gov

Final notes

Because property interests pass on death and courts must bind all interested parties, you generally must add heirs or the estate’s personal representative to a partition action in Michigan. The exact steps depend on whether probate is open, whether heirs are known, and whether minors or incapacitated persons are involved. If you run into difficulty locating heirs, ask the court for guidance on substituted service and guardian ad litem appointment.

Disclaimer: I am not a lawyer and this is not legal advice. This article explains general Michigan law concepts to help you understand your options. For advice tailored to your facts and to help you prepare pleadings or serve parties properly, consult a licensed Michigan attorney.