Quick answer

Yes. If your sibling who owned an interest in real property has died, their heirs (or the personal representative of their estate) must generally be included in a partition action in Maine when those heirs have a legal interest in the property. How you add them depends on whether the decedent’s estate is open, whether the heirs are known, and whether any heirs are minors or legally incapacitated.

Detailed answer — how this works in Maine

Partition is the court process to divide or sell real property when co‑owners cannot agree. In Maine, a partition action must include all parties who have an interest in the property so the court can finally resolve ownership and distribution. That means a deceased co‑owner’s interest does not disappear — it passes to whoever inherits it under the decedent’s will or Maine’s intestacy rules. The court needs those successor owners before it can divide or sell the land and distribute proceeds.

Who should be named as parties?

One of these will usually be appropriate:

• The personal representative (executor/administrator) of the decedent’s estate — if a probate estate was opened. The personal representative stands in for the estate and can be sued or can sue on behalf of the estate.
• The named heirs or devisees (for example: children, spouse, other relatives) — if you can identify them. Those individuals own the decedent’s share and should be parties.
• “Unknown heirs” or a request for substituted service — if you cannot identify or locate heirs after a diligent search. The court may allow service by publication or other substituted means so the case can proceed.

Typical procedural steps

1. Title and ownership check. Perform a title search or check deed records to confirm the decedent’s interest and how title was held (e.g., tenants in common, joint tenancy).
2. Check probate records. See whether a probate estate exists and who the personal representative is. If an estate is open, you can usually join the personal representative instead of naming each heir individually. See Maine Probate provisions (Title 18‑A) for personal representative authority: Maine Probate Code (Title 18‑A).
3. Identify heirs. If no estate exists, search records (death certificate, family records, probate, genealogical sources) to identify likely heirs.
4. Add parties to your complaint. If heirs are known, amend or file your partition complaint naming them. Maine procedure requires joinder of all parties who have an interest so the court can resolve the property rights (see joinder principles under the Maine Rules of Civil Procedure). For joinder of necessary parties, see Maine civil procedure rules: Maine Rules of Civil Procedure.
5. Service of process. Serve each named party according to Maine rules (personal service, certified mail, or other authorized methods). If you cannot find an heir, ask the court for substituted service or service by publication. See Maine rules on service for available methods.
6. If heirs are minors or incapacitated. The court will require a guardian ad litem or a guardian to represent their interests before the court can bind them to a partition outcome.
7. If heirs contest or are unknown. If an heir later appears and claims an interest, the court will decide the claim; if heirs stay absent after proper notice, the court can proceed and bind the property with respect to those properly served or published.

When can you join the personal representative instead of listing heirs?

If a probate administration exists, the personal representative is typically the proper party because the representative has authority to represent the estate’s interest in real property. Naming the personal representative avoids the need to locate every heir immediately and can simplify service and resolution.

What if heirs are unknown or cannot be located?

If you cannot locate heirs after a diligent search, Maine courts permit substituted service — including publication — so the partition can go forward. The court will require proof of your search efforts and will authorize a method of giving notice reasonably calculated to reach the missing parties. If the court approves publication or other substituted service, it may allow the partition to proceed and later resolve claims by appearing parties.

Practical timeline and costs

Adding heirs and handling substituted service can add time and expense. Expect additional months if you must open probate, locate heirs, obtain court permission for substituted service, or appoint guardians ad litem. Costs increase if title research, genealogical searches, or publication in newspapers are required.

Key Maine authorities to review

• Partition practice and the requirement that interested parties be joined — see Maine civil procedure guidance and partition statutes (see partition provisions of Maine law and civil procedure). One place to begin is the Maine statutes and relevant civil rules: Maine Statutes and the Maine Rules of Civil Procedure.
• Personal representative authority and probate procedures — Title 18‑A, Maine Probate Code.

Helpful hints

• Start with a title search: it will show current owners, encumbrances, and often the last recorded deed naming the decedent.
• Check probate first: if a personal representative is appointed, adding that person as a defendant often saves time and avoids having to identify every heir immediately.
• Document your search for heirs: courts expect proof of efforts (death certificate, searches of public records, outreach to family members, probate inquiries) before allowing service by publication.
• Use a certified mail or sheriff’s service where possible for known heirs—this creates a clear record of service.
• If heirs are minors or incapacitated, expect the court to require a guardian ad litem—budget time and fees for that appointment.
• Consider negotiation or mediation with heirs before filing; sometimes heirs will agree to a voluntary partition or sale and distribution, avoiding litigation costs.
• Consult a lawyer early if title is complex, heirs are scattered geographically, or there are competing claims — a lawyer can prepare pleadings, handle service questions, and make sure necessary parties are properly joined so the partition judgment will be final and enforceable.