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  • Writer's pictureDevon Noel Lee

How to Go About Finding Your Illegitimate Ancestor's Father


How to search for illegitimate ancestor's father - genealogy methodology


While a pedigree chart links a person to their parents, a child's parents may never have married in the eyes of the law or the Lord. So how do you go about finding the father of an illegitimate child?


My first reaction is, "Pray the ancestor was Catholic from Mexico or New Mexico."


Why? Well, while indexing and transcribing, I stumbled upon several entries where the priest wrote any of these parental relationship signifiers (hijo natural de, adulterino, espurio, bastardo, or ilegítimo) before the name of the father and mother.

Ta, da! A Father's and mother's name.


You can keep building your family tree.


But sometimes, the child' was listed as "de padre no conocdo" (of father unknown) "expuesta en la casa de Dolores Coral" (abandoned in the house of Dolores Corral).


What then?


Suppose you suddenly discover an unexpected change in the paternity of your ancestors or only see evidence of an unknown father in genealogically relevant documents. What can you do to find the identity of the child's parents in the past?


The following recommendations assume nothing about your genealogy research. Thus, if you see a tree you've already completed, move on to the next and pat yourself on the back for being awesome.



Step 1: Have Descendants Take a DNA Test


We often have to research forward to extend a family branch into the past. The records we have, the better. As such, descendants who have taken DNA tests are very helpful.


Did you notice I said tests - plural?


Andy and I recommend that when you have cases of unknown parentage that you test as many people as you can identify and have them place their DNA in every possible GENETIC genealogy database.


Genetic genealogy databases include Ancestry, 23andMe, MyHeritage, LivingDNA, Family Tree DNA, and GEDmatch. Useful databases DO NOT include My True Ancestry, CRI Genetics, or any other ethnicity testing service.


Now, you might think multiple tests for one person costs a lot of money. That could be true if you're not frugal about it.

  • First, look for sales on Ancestry and 23andMe.

  • After testing with Ancestry and 23andMe, download your RAW DNA and transfer those files to MyHeritage, Family Tree DNA, and GEDmatch. Migrating your DNA results to the first two requires a fee, but the last is free.

  • If you believe you have mostly English ancestors, then you can either test with Living DNA.

  • Request that your fellow descendants of the unknown ancestor make their match results public or grant you access to their accounts to do the research they don't like or want to do.


Let the DNA stuff do its thing for a while as you go about the other steps. But, for now, you're just creating a record and making it available to you.



Step 2: Build Your Family Tre


If you already have your family tree built on Ancestry and MyHeritage, you're fantastic. However, have you made your family tree available to Family Tree DNA, LivingDNA, and GEDmatch? Also, have you begun to build a tree on 23andMe by validating or adjusting their recommended relationships?


Suppose you have your family tree built on all of these platforms based on quality genealogy research. In that case, the genetic genealogy companies can compare your data with our DNA matches to make recommendations. Which we'll come back to later.


HOWEVER, it is not enough to build a family tree to the ancestor with the unidentified relative, particularly one classified as illegitimate.



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We need to review the records which created the profiles and the relationships in our family trees. For example, why research the parental identity of an ancestor if he is not really our ancestor?



Step 3: Create a Profile for the Target Ancestor (and Their Mother]


Take the data about your ancestor with the illegitimate ancestor and put it into an Ancestor Profile or a Research Plan. By taking information out of our database or family trees, we can isolate information about them and stay focused on the methodology.


Review every document for the ancestor to know when and where they were born. See if there are clues to the past hidden in the documents you have previously gathered. You might be surprised that they are already there.


For instance, I discovered the parents of Agnes Anderson after seeing that R P Sparks was an additional informant on her death certificate. (The hospital was her first informant). A newspaper article showed that Sue Oestling sued Robert Sparks for the life insurance policy followiAgnes'es' death. With the full name of Robert Sparks, I soon discovered he was Agnes' brother, and their parents appeared in Rober's records. In summary, the clue to Agnes' parents was in a death record I had had all along. (To read more about this case, start here)


Be sure to include clues from your ancestor, including:

  • Names on marriage records. Sometimes these records have the parents' names or a muddled version of it.

  • Occupations of the father, again potentially on marriage records.

You want to create a similar profile about the mother if known. You want to know:

  • Where was she?

  • Who was she with?

  • What was her social status?

  • What were her economic conditions?

  • How old was she when she became pregnant?

  • And, what was she doing 7-9 months before your ancestor was born?

Prior to the 1970s, a male and female had to be in the same place to create life. Know the time and place so you can recognize possibilities.






Step 4: Understand Illegitimaticy


Did you know that illegitimate means "not recognized as lawful offspring"? Children born to a married couple automatically have this legal relationship established. Couples born to a mother without a father to claim a lawful offspring the child created a problem for the community in which they lived.


In many locations, mothers of illegitimate children struggled to provide for them. As such, the family became a charity case drawing upon the resources of her community.


Did you know that England passed the Bastardy Act of 1733?


Government and church leaders wanted to know the father's identity to reduce the community's financial burden these relationships caused. Therefore, this legislation allowed for the imprisonment of a named father until he provided financially for the child or married the mother.


Do you know of similar laws in the area you're researching? Let me know.


Laws like this are great news for genealogists!


Such laws might mean records if the mother identified the child in a location that required such declarations.


Know the laws regarding reporting of children. In England, a child born after 1837 may have a father listed by an unmarried mother without their knowledge or consent. Hopefully, she didn't include a generic name like John Doe to obscure his identity! After 1875, both the father and mother had to agree to include his name on a child's birth certificate. (Can you guess why?)


It's impossible to discuss all context you'll need to research your ancestor. However, I found the following articles supremely useful.



Genealogy methodology - how to search of illegitimate ancestor's father
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Don't criticize the genealogist using the term illegitimate!


Many people dislike this term and insist that family history researchers stop using it. However, when a genealogist uses the word, it's not a judgment on the child, mother, or father. Instead, the term is a legal definition used at the time of the ancestor's birth.


As stated earlier, the terminology labeling a child as illegitimate in the past include:

  • baseborn

  • spurious

  • bar sinister

  • bastard child

  • bend sinister

  • child born without benefit of clergy

  • natural child

  • reputed child

  • imputed child

  • child born in the vestry

  • abandoned child.


Different languages and cultures have other terms. As mentioned earlier, Spanish records said hijo natural de, adulterino, espurio, bastardo, or ilegítimo.



Latin used "ignotus" (unknown), "fulius populi" (unidentified local man), and "filius mullius" (stranger or unknown man).


What terms define illegitimate births in the language you're researching? Let me know below.


Before we move on, recognize that a couple might have a reason for not marrying before the birth of a child. For example, in some cases, a couple became married in the eyes of a community, but a traveling minister wasn't on hand to marry them. As such, they began their family and married as soon as the minister came 'a callin'.


Sometimes the couple wasn't allowed to marry because churches handled the ceremonies, and they belonged to no church in the region they lived. Read this article for more reasons why a couple might not have married.


Research the lives of your specific child and mother and the culture and customs of the time and place they lived. You might discover a few unexpected details.


Step 5: Consult the Following Resources


  • Church records - I've alluded to this earlier, but church records could hold the clue to your ancestor's parents. Be sure to consult baptismal or marriage records for the child (and any known siblings). Also, search for church meeting minutes, membership records, and any records that might include censor or ex-communication of the child's mother.

  • Oral History - reach out to descendants of the known ancestor. What do they know about the ancestor's parentage? Some descendants know nothing. Others change the subject because illegitimacy is still taboo for many. A few may know something that can help you climb your tree.

  • Naming Patterns - A mother might name the child, or the child might name one of their children after the father. Typically, illegitimate children receive their mother's surname, even if the father is identified. For example, it's possible that a mother, Elizabeth Corey, named her son John Jamieson Corey. Thus, John Jamieson might be the father of her child.

  • Newspapers - They aren't called rag sheets for nothing. Newspapers, particularly issues around the time of your ancestor's birth, may include a derogatory statement about your ancestor's mother. It may consist of who was in the mother's social circle providing clues for potential fathers. In the more sensitive cases, the mother might appear in an article describing violence committed against her person.

  • Probate and Estate records - This one may be difficult if you do not have a potential father. However, if you have two men who could be a child's father, see if the probate files mention the child as an heir.

  • Court Records - Look for court records that involve the mother and the child. Search for petty or civil cour sessions for failure to pay financial obligations, disputed paternity, assault, rape, or fraud. Also, search records regarding orphans and guardianships.

  • Bastard Records - Around the world, many locations created bastardy documents. Whether they are bastardy bonds or bastard examinations, consult these resources. They often identify the father, mother, child and detail their financial agreements.

  • Apprentice Bonds - In the past, some children became apprentices. A document may define the apprenticeship contract. Review the name of whoever paid the indenture. Perhaps this is a clue to the father's identity.

  • Workhouse Records - Since single mothers struggled to provide for their families, investigate workhouse records. While these documents typically don't include the father's name, they can offer you historical context to the life of your ancestor in their early years. Or investigate any settlement involving the mother. Maybe you can determine the father's identity after all.

  • Records of Corrected Entries - I found this tip courtesy of BeSpoke Genealogy. For Scottish babes born after 1855, an update to their birth could appear in the RCE (Register of Corrected Entries) reference. These entries happen if the parents married after the birth or the mother won a paternity case in the courts. So cool! Check out Scotland's People for this resource.

I'm sure there are other resources you can consult to find the identity of an unknown father. Let me know in the comments which ones I'm missing.


Step 6: Research the Men in Mom's Life


Develop a potential father list by identifying the men in your Mom's life. List all the men she:

  • Live with

  • Lived near

  • Socialized with

  • Worked for

Sometimes the man was a boarder, a family member, a family friend, an immigrant, or someone new in the area. On the other hand, they could be someone who worked at the same office or company. In some cases, servants were wooed by the men of the household in which they worked. They could be much older than she or even younger.


With this list, see if any of the men's names show up on the DNA match list that should now be ready from Step 1. If you're lucky, you'll find a few theories, and then you can begin triangulating DNA to validate a hypothesis.



Step 7: Research the Men on Your DNA Match's Trees


If you're fortunate to have found a potential man by this step, as was the case with my grandmother's father, you then are ready to consult the available family trees of your DNA matches. Very briefly, you'll want to:

  • Identify the matches that could not be related through your illegitimate ancestor and exclude them from further scrutiny.

  • For those related to potentially related to the unknown parent:

    • Use 23andMe's Genetic Based Family Tree Builder to see how your DNA matches may fit into your family tree.

    • Review the family trees linked to DNA matches on Ancestry or MyHeritage. Gather a list of surnames from the likely generation in which your ancestor lived that are of an age and in place to have met the mother.

  • Compare the possible surnames to names of individuals in your mother's circle. Did you recognize any names?

  • Research the men on the "potential list" to see if they

    • Worked with your ancestor's mother

    • Worshipped with her

    • Was stationed in the military in the same town.

    • Attended college or university in the same town.

  • Rule out any gentleman who could not have been near your ancestor's mother at the right time to create life.


Hopefully, you'll have enough to find your illegitimate ancestor's father. If that doesn't work, see if these ideas for researching parents of adopted children work for you.


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