Disclaimer: This article does not constitute legal advice. It provides general information under Colorado law. Consult a qualified attorney for guidance tailored to your situation.

Detailed Answer

1. Statutory Framework

Under Colorado law, a personal representative must take “due diligence” to locate and notify all heirs, including those unknown at the start of probate. Key provisions appear in C.R.S. § 15-12-801 through § 15-12-803 (see Colorado Revised Statutes, Title 15, Article 12).

2. What Courts Expect

Courts require documented, good-faith efforts. If heirs remain missing, you must publish notice. If you later identify an heir, you must promptly notify them by mail or personal service. You must file proof of your efforts with the court.

3. Due Diligence Steps

Review the decedent’s personal papers, family Bible and correspondence for clues about relatives.
Search public records: birth certificates, marriage licenses, death records, deeds and probate files in relevant Colorado counties.
Contact known relatives or close family friends to get names, addresses and last-known locations of potential heirs.
Consult online databases and genealogical resources, such as the Colorado State Archives or reputable ancestry sites, to trace family lines.
Send certified letters to all known or suspected heirs; keep return receipts or proof of delivery.
If you cannot locate an heir after reasonable inquiry, publish a summary notice once a week for three consecutive weeks in a newspaper of general circulation in the county where the estate is administered (C.R.S. § 15-12-803).
File an affidavit with the court listing all your searches, mailings and publication details.

4. Example Scenario

Jane Doe dies intestate in Denver County. The personal representative:

Reviews Jane’s address book, identifying a cousin Jane mentioned.
Visits Denver Vital Records for birth and marriage certificates.
Emails the cousin, who refers them to another branch of the family in Colorado Springs.
Sends certified letters to all relatives provided, and publishes notice in the Denver Post for three weeks when one cousin’s address bounces back.
Submits a detailed affidavit to the probate court, then notifies the newly located cousin by certified mail.

Helpful Hints

Keep a centralized log of all contacts, searches and publications.
Use county clerk and recorder offices to obtain property and court records.
Check social media or professional networking sites for current addresses.
Consider hiring a genealogist or private investigator for complex family trees.
Maintain transparent communication with the court to avoid delays or objections.