All genealogists should be asking this question for every single relationship between people in their trees – or at least for every person that they claim as an ancestor. The answer differs a bit when you introduce DNA into the equation, so let’s discuss this topic.

It’s easier to begin by telling you what proof IS NOT, rather than what proof is.

What is Proof, Anyway?

First of all, what exactly do we mean by proof? Proof means proof of a relationship, which has to be proven before you can prove a specific ancestor is yours. It’s a two-step process.

If you’re asking whether those two things are one and the same, the answer is no, they are not. Let me give you a quick example.

You can have proof that you descend from the family of a specific couple, but you may not know which child of that couple you descend from. In one case, my ancestor is listed as an heir, being a grandchild, but the suit doesn’t say which of the man’s children is the parent of my ancestor. So frustrating!

Conversely, you may know that you descend from a specific ancestor, but not which of his multiple wives you descend from.

You may know that your ancestor descends from one of multiple sons of a particular man, but not know which son.

Therefore, proof of a relationship is not necessarily proof that a particular person is your ancestor.

Not Proof of an Ancestor

OK, so what’s NOT proof? Here are a dozen of the most common items – and there are surely more!

1. Proof is not a DNA match alone. You can match as a result of ancestors on any number of lines, known or unknown.
2. Proof is not an oral history, no matter how much you want to believe it or who said it. Oral history is a good starting point, not an end point.
3. Proof is not, not, 1000 times NOT someone else’s tree. A tree should be considered a hint, nothing more.
4. Proof is not a book without corresponding evidence that can be independently corroborated. Being in print does not make it so, people make mistakes and new information surfaces.
5. Proof is not a man by the name of Jr., meaning that he is the son of a man by the same name with the suffix of Sr. Sr. often means older and Jr. means younger, but not necessarily related. Yes, this has bitten me.
6. Proof of a father/son relationship is not two men with the same name in the same location.
7. Proof is not a Y DNA match, at least not without additional information or evidence, although it’s a great hint!
8. Proof is not an autosomal DNA match, unless it is an extremely close match and even then you (probably) need additional information. For example, if you have a half-sibling match, you need additional information to determine which parent’s side.
9. Proof is not an Ancestry Circle, at least not without additional information.
10. Proof is not similar or even identical ethnicity, or lack thereof.
11. Proof is not a “DNA Proven” icon, anyplace.
12. Proof is not a will or other document, at least not alone, and not without evidence that a person by the same name as the child is the RIGHT person.

I learned many of these NOTS or KNOTS as I prefer to call them, because that’s what they tie me in, by ugly experience. I began genealogy before there were proof standards, let alone the GPS (Genealogical Proof Standard). DNA adds yet another dimension to existing paper standards and is an important aspect of the requirement for a “reasonably exhaustive search.” In fact, there is no reason NOT to include DNA and I would suggest that any genealogical search is not complete without including genetic evidence.

Proof Is a Two-Way Street

Using traditional genealogy, genealogists must be able to prove not only that an ancestor had a child by a specific name, but that the person you believe is the child, is indeed the child of that ancestor.

Let me use an example of Daniel, the son of one Philip Jacob Miller in Washington County, Maryland in 1783.

The tax list shows Philip J. Miller, 15 entries from the bottom of the page, shown below. It also shows “Daniel Miller of Philip” 6 entries from the bottom, and it’s our lucky day because the tax list says that Daniel is Philip’s son.

But wait, there’s another Daniel, the bottom entry. If you were to look on the next page, you would also notice that there’s a Philip Miller who does not own any land.

What we have here is:

• Philip J. Miller, with land
• Daniel, son of Philip, no land
• Daniel, no father listed, land
• Philip, no land

This just got complex. We need to know which Philip is Daniel’s father and which Daniel is which Philip’s son.

Establishing proof requires more than this one resource.

The great news about this tax list is that it tells us how much land Philip J. Miller owned, and utilizing other resources such as deeds and surveys, we can establish which Philip J. Miller owned this land, and that his name was indeed Philip Jacob Miller. This is important because not only is there another Philip, who, by the way, is NOT the son of Philip Jacob Miller (knot #6 above), there is also another Jacob Miller, who is NOT Philip Jacob Miller and who isn’t even related to him on the Miller line, according to the Y DNA of both men’s descendants.

How would we prove that Philip Jacob Miller is the father of Daniel Miller? We’d have to follow both men backward and forward in time, together. We have great clues – land ownership or lack thereof.

In this case, Philip Jacob Miller eventually sells his land. Philip Jacob Miller also has a Bible, which is how we know that there is no son named Philip. Philip Jacob’s son, Daniel leaves with his brother David, also on this tax list, travels to another location before the family is reunited after moving to Kentucky years later, where Philip Jacob Miller dies with a will. All of his heirs sign property deeds during probate, including heirs back in Frederick and Washington County, Maryland. There is enough evidence from multiple sources to tie these various family members from multiple locations conclusively together, providing two way proof.

We must be able to prove that not only did Philip Jacob Miller have a son Daniel, but that a specific Daniel is the son of that particular Philip Jacob Miller. Then, we must repeat that exact step every generation to the present to prove that Philip Jacob Miller is our ancestor.

In other words, we have a chain of progressive evidence that taken together provides conclusive proof that these two men are BELIEVED to be related. What? Believed? Don’t we have proof now?

I say believed, because we still have issues like unknown parentage, by whatever term you wish to call it, NPE (nonpaternal event, nonparental event,) or MP (misattributed parentage,) MPE (misattributed paternal or parental event) or either traditional or undocumented adoptions. Some NPEs weren’t unknown at the time and are results of situations like a child taking a step-parent’s surname – but generations later – having been forgotten or undocumented for descendants, the result is the same. They aren’t related biologically in the way we think they are.

The Big Maybe

At this point, we believe we have the Philips, Philip Jacobs and Daniels sorted correctly relative to my specific line. We know, according to documentation, that Daniel is the son of Philip Jacob, but what if MY ancestor Daniel ISN’T the son of Philip Jacob Miller?

• What if MY ancestor Daniel just happens to have the name Daniel Miller and lives in the same geography as Philip Jacob Miller, or his actual son Daniel, and I’ve gotten them confused?
• What if MY ancestor Daniel Miller isn’t actually my ancestor after all, for any number of reasons that happened between when he lived and died (1755-1822) and my birth.

If you think I’m being facetious about this, I’m not. Not long after I wrote the article about my ancestor Daniel Miller, we discovered another Daniel Miller, living in the same location, also descended from the same family as evidenced by BOTH Y and autosomal DNA. In fact, there were 12 Daniel Millers I had to sort through in addition to the second Daniel on the 1783 tax list. Yes, apparently Daniel was a very popular name in the Miller family and yes, there were several male sons of immigrant Johann Michael Muller/Miller who procreated quite successfully.

Enter DNA

If DNA evidence wasn’t already a factor in this equation, it now must come into play.

In order to prove that Philip Jacob Miller is my ancestor, I must prove that I’m actually related to him. Of course, the methodology to do that can be approached in multiple ways – and sometimes MUST be approached using different tools.

Let’s use an example that actually occurred in another line. Two males, Thomas and Marcus Younger, were found together in Halifax County, Virginia, right after the Revolutionary War. They both had moved from Essex County, and they consistently were involved in each other’s lives as long as they both lived. They lived just a couple miles apart, witnessed documents for each other, and until DNA testing it was believed that Marcus was the younger brother of Thomas.

We know that Marcus was not Thomas’s son, because he was not in Thomas’s will, but Marcus and his son John both witnessed Thomas’s will. In that time and place, a family member did not witness a will unless it was a will hastily constructed as a person was dying. Thomas wrote his will 2 years before it was probated.

However, with the advent of DNA testing, we learned that the two men’s descendants did not carry the same Y DNA – not even the same haplogroup – so they do not share a common paternal ancestor.

Needless to say, this really threw a monkey wrench into our neat and tidy family story.

Later, the will of Thomas’s father, Alexander, was discovered, in which Marcus was not listed (not to mention that Alexander died before Marcus was born,) and, Thomas became the guardian of his three sisters.

Eventually, via autosomal DNA, we proved that indeed, Marcus’s descendants are related to Thomas’s descendants as well as other descendants of Thomas’s parents. We have a proven relationship, but not a specifically proven ancestor. In other words, we know that Marcus is related to both Thomas and Alexander, we just don’t know exactly how.

Unfortunately, Marcus only had one son, so we can’t confirm Marcus’s Y DNA through a second line. We also have some wives missing from the equation, so there is a possibility that either Marcus’s wife, or his unknown biological father’s family was otherwise related to Alexander’s line.

So, here’s the bottom line – we believe, based on various pieces of compelling but not conclusive evidence that Marcus is the illegitimate child of one of Thomas’s unmarried sisters, who died, which is why Marcus is clearly close to Thomas, shares the same surname, but not the Y DNA. In fact, it’s likely that Marcus was raised in Thomas’s household.

• It’s entirely possible that if I incorrectly listed Thomas as Marcus’s father on Ancestry, as many have, that I would be placed in a Thomas circle, because Ancestry forms circles if your autosomal DNA matches and you show a common ancestor in your trees. This is why inclusion in a circle doesn’t genetically confirm an ancestor without additional information. It confirms a genetic relationship, but not how a person is related.
• It’s entirely possible that even though Marcus’s Y DNA doesn’t match the proven Y DNA of Thomas, that Marcus is still closely related to Thomas – such as Marcus’s uncle. That’s why Marcus’s descendants match both Thomas’s and Alexander’s descendants through autosomal testing. However, without Y DNA testing, we would never know that they don’t share a paternal line.
• It’s entirely possible that if Marcus was supposed, on paper, to be Thomas’s child, but was fathered by another man, such as his wife’s first husband, I would still be in the circle attributed to both Thomas and his wife, by virtue of the fact that I match DNA of Thomas’s descendants through Thomas’s wife. This is your classic step-father situation.

Paper is Not Proof

As genealogists, we became so used to paper documentation constituting proof that it’s a blow when that paper proves to be irrelevant, especially when we’ve hung our genealogical hat on that “proof” for years, sometimes decades.

The perfect example is an adoption. Today, most adoptions are through a court of law, but in the past, a functional adoption happened when someone, for whatever reason, took another child to raise.

The history of that “adoption” although not secret when it happened, became lost in time, and the child is believed to be the child of the couple who raised them. The adoption can actually be a step-parent situation, and the child may carry the step-father’s surname but his own father’s Y DNA, or it can be a situation where a relative or unrelated couple raised the child for some unknown reason.

Today, all paper genealogy needs to be corroborated by DNA evidence.

DNA evidence can be some combination of:

• Y DNA
• Autosomal DNA
• Mitochondrial DNA

How Much Proof is Enough?

One of my favorite saying is “you don’t know what you don’t know.”

People often ask:

1. If they match someone autosomally who shares the same ancestor, do they really need to prove that line through Y or mitochondrial DNA?
2. Do they really need to match multiple people?
3. Do they really need to compare segments?

The answers to these is a resounding, “it depends.”

It depends on the circumstances, the length of time back to the common ancestor, and how comfortable you are not knowing.

Relative to question 1 about autosomal plus Y DNA, think about Marcus Younger.  Without the Y DNA, we would have no idea that his descendant’s Y DNA didn’t match the Thomas Younger line. Suddenly, Marcus not being included in either Thomas nor Alexander’s will makes sense.

Relative to question 2 about matching multiple people, the first cousin we tested to determine whether it was me or my brother that was not the child of our father turned out to have different Y DNA than expected. Thank goodness we tested multiple people, including autosomal when it became available.

Relative to question 3 about comparing segments, every matching segment has its own unique history. I’ve encountered several situations where I match someone on one segment from one ancestor, and another segment from an entirely different line. The only way to determine this is by comparing and triangulating individual segments.

I’ve been bitten so many times by thinking I knew something that turned out to be incorrect that I want every single proof point that I can obtain to eliminate the possibility of error – especially multiple kinds of DNA proof. There are some things that ONLY DNA can reveal.

I want:

• Traditional documentary evidence for every generation to establish the actual paper trail that proves that the child descends from the proper parents.
• Y DNA to prove the son is the son of the father and to learn about the deeper family history. For example, my Lentz line descends from the Yamnaya culture, something I would never have known without the Big Y DNA test.
• Mitochondrial DNA to prove that the mother is the actual mother of the child, if possible, not an unknown earlier or later wife, and to learn about the deeper family history. Elizabeth Mehlheimer’s mitochondrial DNA is Scandinavian – before her ancestors are found in Germany.
• Autosomal DNA to prove that the paper lineage connecting me to the ancestor is correct and the line is not disrupted by a previously unknown adoption of some description.

I attempt to gather the Y and mitochondrial DNA haplogroup of every ancestor in my direct line if possible and confirm using autosomal DNA.

Yes, my personal proof standard is tough, but I suggest that you at least ask these questions when you evaluate documentation or see someone claim that they are “DNA proven” to an ancestor. What, exactly, does that mean and what do they believe constitutes proof? Do they have that proof, and are they willing to share it with you?

Genealogical Proofs Table

The example table below is designed to be used to document the sources of proof that the individual listed under the name column is in fact the child of the father and mother shown. Proofs may vary and could be personal knowledge (someone you knew within your lifetime), a Bible, a will, a deed, an obituary, death certificate, a church baptismal document, a pension application, census records, etc. DNA confirmation is needed in addition to paper documentation. The two types of proof go hand in hand.  

If you’d like to read more about the difference between evidence and proof, and how to get from evidence to proof, check out this article, What is proof of family history? by my cousin, retired attorney, Robin Rankin Willis.

Proof is a Pain!

So now that we’ve discussed what proof is not, and what types of records constitute proof, you may be thinking to yourself that proof is a pain in the behind. Indeed, it is, but without sufficient proof, you may literally be doing someone else’s genealogy or the genealogy of an ancestor that’s not your own. Trust me, that’s infinitely more painful.

I hate sawing branches off of my own tree. If I have to do it, the sooner I make the discovery and get it over with, the better.

Been there, done that, and really, I don’t want the t-shirt.

There is never such a thing as “too much” proof, but there is certainly too little. We are fortunate to live in a time when not only are historical records available, but the record passed by our ancestors inside our very cells tells their story. Use every tool and every type of DNA at your disposal! Otherwise, you get the t-shirt:)

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