3. Intro to Genealogy: Common Mistakes Beginner Genealogists Make (And How to Avoid Them)

I am not one to use vulgar language in any way. Nevertheless, my father taught me an age old saying that sticks with me to this day, and it perfectly conveys the message I wish to convey in this blog post. He wrote the word ASSUME on a piece of paper and declared the following, pointing to each letter in the word: "When you ASSUME, you make an ASS out of U and ME."

Unfortunately, genealogists can be the biggest "asses."

With a plethora of online public ancestry trees and research available, most of the common mistakes many genealogists make (myself included) involve assuming something to be correct without completing proper research to confirm those assumptions.

The earlier you learn to spot and avoid these common pitfalls, the stronger—and more rewarding—your family tree research will be. In this post, I’ll share four of the most frequent beginner mistakes I see (and made myself!), along with tips to help you stay on the right track.

Assumption #1: Every “John Smith” Is Your John Smith

One of the trickiest parts of genealogy is dealing with name repetition. Our ancestors weren’t all that creative—chances are, there were a dozen Johns, Marys, or Williams in every town, and they often reused family names across generations. And this is not just true of American cities and names: my uncle visited our ancestors' home country - Germany - to find that the phonebook was filled with pages and pages of people bearing our ancestors' surname.

The first mistake:

Finding someone with the “right” name and plugging them into your tree without verifying they’re truly your ancestor, or assuming every Jones in a township must be a distant relative.

How to avoid it:

• Always cross-check multiple pieces of evidence: location, age, occupation, spouse/children, and other context clues.

• Use a timeline to see if your ancestor’s movements and life events match the record.

• Be especially cautious when working in large cities or with common surnames.

• Research what common names may have existed in your ancestors' cultural groups and heritage.

📝 Pro Tip: Middle initials, unique first names, and even unique occupations in the household can help distinguish families in census or directory records.

This can often lead to another assumption - merging people who seem the same, but aren't. But small details can tell a very different story.

The second mistake:

Combining records from two different individuals and treating them as one.

How to avoid it:

• Use marriage, death, and probate records to confirm relationships.

• Pay close attention to occupations, family members, and neighbors.

• Build timelines to detect inconsistencies—if your ancestor was supposedly married to two different people at the same time, something’s likely off.

  
  

📝 Pro Tip: Always be open to the idea that you’ve made a wrong connection. Rechecking your work is a sign of a careful researcher, not a failure.

Family groups are especially helpful when dealing with name repetition. It's highly likely that two John Smiths lived in the same township. It's less likely that both John Smiths were married to an Ann Bergeron (but still not impossible!) Cross-referencing records that can document more than one person in a family (like census and directory records) is an essential step to ensuring you avoid making this kind of mistake.

Assumption #2 - Copying Online Trees Without Verification

It's so tempting. You find a public tree with 10 generations of your family already mapped out—photos, dates, even documents attached. It feels like you’ve struck gold. Surely the researcher did their due diligence before publishing their research online? (Spoiler: not always.)

The mistake:

Treating other people’s online trees as fact without checking the sources. Take every online source with a grain of salt.

How to avoid it:

• Use other trees as clues, not confirmed truth.

• Follow up by finding the original records cited (if there are any).

• If a tree doesn’t list sources, proceed with caution—don’t take it at face value.

📝 Pro Tip: Even if someone else has “done the work,” it doesn’t mean it’s correct. Misinformation spreads quickly in genealogy.

One of my first days as a novice genealogist, I found an online family tree on Ancestry.com claiming my ancestors were direct descendants of Charlemagne. I thought I had hit the ancestry jackpot. I combed through the public tree for hours, saving ancestor after ancestor to my own tree to share with my family. Finally, I saved an "ancestor" whose dates of birth and death were not logically possible with the information I had about his children.

After a bit of digging, I found there were two men with the same name in the region, and it was highly likely that the original tree owner had assumed they were the same person. That genealogist made Assumption #1, but I had fallen into the trap of Assumption #2. I'm still not positive if we're related to Charlemagne. It's still on my to-do list of family mysteries to tackle.

Assumption #3 - Ancestry Hints = Facts

Just as tempting as the public trees are those little green leaves that pop up conveniently on each ancestor's Ancestry.com profiles. Hints are exciting and a convenient resource to your research. It's like Ancestry.com is doing the hard work of scanning through records for you! Nevertheless, these are not confirmed hints. They are simply suggestions generated by an algorithm that looks for similarities in names, dates, and locations. And as every genealogist quickly learns, similarities are not proof.

The mistake:

Assuming every hint actually pertains to your ancestor and saving a record without evaluating it for yourself.

How to avoid it:

• Evaluate every record, photo, tree, etc., that pops up.

• Treat every hint as a potential lead, but not a confirmed match.

• Cross-check the hint with multiple sources.

• Pay attention to contradictions in locations, ages or dates, names, or relationships.

📝 Pro Tip #1: Make a habit of marking "maybe" on any hints you have even a sliver of doubt about. You can always return to these hints when you have more information about your ancestor.

📝 Pro Tip #2: Contradictions don't necessarily mean that a hint isn't a match. Remember - records are subject to human error, and most were not created for the future genealogist. Expect a range of dates, for example, and not always the exact year you're expecting.

📝 Pro Tip #3: Don't be afraid of searching through a record yourself. Ancestry's algorithm isn't perfect, and their indexes are not always accurate. If you know an ancestor should be in Dallas in 1964, check the directories yourself! Don't rely on the algorithm to find it for you.

Assumption #4 - I Don't Need Source Citations

Citing sources might not be the most exciting part of family history, but trust me—it’s one of the most important.

The mistake:

Not keeping track of where you found each piece of information (or relying on memory to remember it later).

How to avoid it:

• When you find a record, save a link, screenshot, or reference note with the document name, date, and location.

• Use the citation tools offered by sites like Ancestry and FamilySearch—they do the heavy lifting for you.

• Even a basic note like “1940 U.S. Census, Dallas County, TX” is better than nothing.

📝 Pro Tip: Good citations not only help you stay organized, they make it easier to spot errors and retrace your steps.

If your research or your education is not ready for in-depth citations, that's okay. Ancestry.com and FamilySearch allow you to save records directly to each profile, so some people may not find the need to write down every detail of every record at the start. As long as you have a system for you and others to find your research later on!

Genealogy Is a Marathon, Not a Sprint

Genealogical research is exciting—but it takes time, patience, and a healthy dose of skepticism. Mistakes happen (even to professionals!), but knowing what mistakes you can avoid will help make your research stand the test of time.

Take your time. Follow the evidence. And don’t be afraid to hit the brakes when something feels off.

Need help reviewing your tree or untangling a brick wall? Let’s work together! Contact me for a consultation, or drop a comment below with a research challenge you’ve faced.

And don’t miss the next post in the Intro to Genealogy series: Understanding the Genealogy Research Process.