The real work with mirror trees is not in creating them, but what you do with them once they are created. If you have created a mirror tree, and do not know how to use it to discover those hard-to-find family members, then you are at the right blog.
Here are 5 steps to use a mirror tree to find ancestors for those with unknown parentage:
Step 1. Create a mirror tree
Follow the 5 Steps to create a mirror tree from the last blog post.
Step 2. Explore shared ancestor hints
Once your mirror tree has ancestors back several generations you should start to see shared ancestor hints from your AncestryDNA home page. These hints highlight the people that share DNA with you that also have ancestor(s) in their tree that matches those in your mirror tree. These shared ancestor hints will help you to identify which ancestor you and your DNA cousin share.
To see if you have any shared ancestor hints, look at the ‘DNA Matches’ section of your AncestryDNA home page (see image below). This section offers three summary statistics which count how many Shared Ancestor Hints, Starred matches, and 4th cousins or closer are associated with your DNA.
If the DNA cousin you linked your DNA to has their DNA linked to a family tree, then you should at least see one shared ancestor hint on your AncestryDNA home page. If you gathered the ancestors for your mirror tree from a source other than a linked tree of your DNA cousin, then you may initially see a ‘0’ next to these hints. Sometimes it takes time for Ancestry’s algorithm to identify these matches, but I found that they usually show up within 24 hours from when a new ancestor is added to the mirror tree.
To explore the shared matches, click on the ‘View All DNA Matches’ button under the DNA match summary statistics. This will bring you to a list of the people that Ancestry thinks are genetically related to you (see image below). By default these are sorted from closest relatives to most distant relatives. There are filter options near the top of this page that allows you to only show the DNA cousins that either have shared ancestor hints, are new, or are starred.
Select the ‘hints’ filter tab to see which of these cousins have direct ancestors in their tree that match those of your mirror tree. To see the common ancestor a matched cousin has with your mirror tree, click on the ‘View Match’ button. The common ancestor will be revealed as well as a side-by side comparison of how your mirror-tree cousin and the matched DNA cousin relate to this common ancestor (see image below).
If there are identical surnames in the DNA cousin’s tree to your mirror tree, they will be listed below the shared ancestor description. Clicking on these surnames will give you a side-by-side comparison of the ancestors with the surname in the two trees. Look carefully at these ancestors, because sometimes they are the same and show other common ancestors.
Possible reasons your mirror tree may not have any shared DNA matches (or only the one from the DNA cousin the tree was derived from) is because:
- The mirror tree is not filled out completely
- The mirror tree is filled out incorrectly (identified wrong ancestors)
- You do not have a lot of DNA Cousins to work with.
- The mirror tree does not have enough generations of ancestors
If you find yourself in this situation, it could be a very frustrating, but I encourage you to keep trying.
To get more productivity from these more frustrating mirror trees try to:
- review all of the people in your tree to identify and correct any errors
- take the ancestors back another generation
- wait for more people to DNA test with Ancestry.
If these actions do not get you more shared ancestor hints, then you may want to take a break from this mirror tree, and try to start a new one from a different close DNA cousin cousin.
Step 3. Identify the ancestor you share with the mirror tree cousin.
Now that you have some shared match hints, and have identified potential common ancestors, you want to identify which ancestor you and the DNA cousin from the mirror tree have in common. If it is clear from your work in step 2 who this common ancestor is, then you can skip this step. Otherwise, it helps to create a visual aid of the shared ancestor hints that I call a Shared Ancestor Map.
To create this map, print or take a screen capture of your mirror tree, and mark all of the ancestors on the tree that are also listed in the trees of your DNA shared matches from step 2. This will allow you to see a pattern of lineage. Usually it will be linear, and point you towards an ancestor that you most likely descend from.
Below is an image of an example of a shared ancestor map I created for a mirror tree based off of a 4th cousin DNA match to my mother. This mirror tree had three shared DNA matches. One of the matches was the 4th DNA cousin that was used to create the mirror tree. The other two matches were estimated as 5th-8th DNA cousins and had two different ancestors in common with the mirror tree. I shaded these common ancestors on the mirror tree (see below), and was happy to see that they formed a line.
Since the mirror tree in the example above is derived from a 4th cousin match, I expect the common ancestor between the 4th cousin and my mother to be a 3rd great grandparent. This shared match map suggests that this common ancestor is a parent of Martha Elizabeth Holt. Through research, I was able to identify these parents whom both or one, my Mom likely descends from.
Step 4: Build the mirror tree from the identified common ancestor
Now that an ancestor has been identified that both you and your mirror cousin descend from, you can use this ancestor as a new reference point for your mirror tree. You are likely a descendant of one of the children of the ancestor identified in step 3, but may descend from one of their siblings. First, build the mirror tree up by adding the parents and grandparents of the new reference ancestor. Then build the mirror tree down by adding all of the children of the common ancestor. Make sure to add the spouses of these children to the mirror tree as well as the spouse’s parents and grandparents.
Choose one of the children that is not the child already identified as an ancestor of your mirror cousin, and link your DNA to that child. Wait 24 hours or so and check your shared ancestor hints. They should differ from the hints you had before when your DNA was linked to the cousin you built the tree from. Create a new shared DNA map with these hints and see if any patterns lead to further clues to your direct parentage.
If you find matches on the spouses’ ancestors, then this child and spouse are your direct ancestors (grandparents). If not, try linking your DNA to another child, and see if there are additional shared ancestor hints and if you match their spouses’ ancestors . If you do not match any of the children’s spouses, then the child that gives you the most DNA hints when your DNA is linked to them, is most likely the one that you descend from.
Below is an example of a shared ancestor map for a child of the common ancestor that was identified from my 4th cousin mirror tree in the example from step 3. When I linked my Mom’s DNA to the child, Mary Madeline Holt, I received 7 shared DNA matches that allowed me to shade in almost all of the ancestors on the newly created shared ancestor map. This confirmed to me that I was on the right trail, and my mother was very likely a descendant of William Holt and Martha Ridley. Some of the shared matches listed Mary Holt as the common ancestor, which led me to believe that she was likely my Mom’s 2nd Great Grandmother.
Step 5. Repeat steps 3 and 4
Once you identify which child of the original identified common ancestor you descend from, you want to make them your new reference point in the mirror tree. Their parents, grandparents, and possibly great grandparents are already in your mirror tree so there is no need to build the tree up from this new reference point. But you will need to build their tree down another generation by finding and adding their children, children’s spouses, and the spouses parents to the mirror tree. Then link your DNA to one of these newly added children, check for new shared ancestor hints, create a shared ancestor map, and see which hints guide you to your next likely grandparent.
This process should be repeated until you get to the generation of the parent you are hoping to identify with the mirror tree. If you know the date and location of where your ancestor with unknown parentage was born, then use this information to guide you to whom to link your DNA to.
Continuing with the 4th cousin mirror tree example from above, I repeated steps 3 and 4 two times until I found the potential father (William Norsworthy Gordon) of my ancestor with unknown parentage (my maternal grandfather). The real clues for this example is when I received shared match hints for the ancestors of the spouses of the reference ancestor (who the DNA was linked to). This was very helpful since these ancestors that the DNA was linked to had multiple spouses.
Congratulations, you now can use a mirror tree to help you identify potential biological ancestors for someone with unknown parentage. This is a complicated process that makes most sense when you apply it to your own genetic research. The more mirror trees you create and are successful with, the easier and simpler the process becomes.
Once you have identified potential parents of an elusive ancestor, you can try to contact living descendants to see if they are willing to take a DNA test to confirm the genetic relationship. I am currently waiting on DNA results of a direct descendant of William Norsworthy Gordon to see if he is indeed my great grandfather.
If you or anyone you know have questions about creating or analyzing mirror trees please leave a question or comment below, and I will help as much as I can.