Shared DNA Matches | Solve a Mystery

Melanie Mohler

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Shared DNA matches can help solve mysteries! Here’s how Robbi used her shared match list to find her grandfather’s true identity–and the story behind his separation from his parents overseas.

Robbi began doing traditional genealogy more than 20 years ago, and for the most part, her family lines were easy to follow, except for her paternal grandfather. From the 1930 U.S. Census and his marriage certificate, Robbi was able to piece together that he was born John Henry Anderson on July 15, 1885 in Greenock, Scotland to William Anderson and Esther Maria Hill, also born in Scotland. John later emigrated to the U.S. around 1920 and married Agnes Hughes in 1922. Robbi searched for John on Ancestry, Scotland’s People, Findmypast, and military records, but couldn’t find him.

Robbi took a DNA test in 2016. She was able to easily match and find how she was related to matches on her mother’s and paternal grandmother’s side. But there was a group of about 20 people at the 2nd-3rd cousin level that all tied back to a most recent common ancestor couple by the last names of Barrett/Barratt and Trevor. Robbi could see how all these people were related to each other, but she couldn’t figure out where her grandfather fit in (and by extension, her father and herself).

In 2021, Robbi’s paternal first cousin Alan took a DNA test, and he matched with the same mystery line that Robbi did. During a coaching session with Diahan Southard, Diahan suggested that Robbi add Alan to her WATO tree and focus on his results.

Reviewing Shared DNA Matches

More recently, Robbi joined the Your DNA Guide DNA Study Group. During the Study Group, she was encouraged to revisit her cousin Alan’s matches and dot groups again. Robbi discovered a match that both she and Alan share at the 2nd-3rd cousin level. Robbi had spent a lot of time looking at the shared matches between her and this match, Mark, but she hadn’t recently taken a deep dive on the list of shared matches between Alan and Mark.

She looked at some of the public trees. The tree from a match named G.W. had an Esther Maria Hill. (Robbi later realized she also matched with G.W., but only at 19cM). Remember that name? It’s the same name Robbi found for her ancestor John’s mother, from Scotland. While Esther’s name and age fit, the woman on this tree was born and lived in Staffordshire, England and was married to a William Banks, not a William Anderson.

Robbi reached out to a few people who had hints for this Esther. One match, Jackie, proved extremely helpful. Jackie responded that Esther was her great-great-grandmother and that, while she did not know of any Andersons, she was descended from John Barrett and Sarah Trevour–the same pair of surnames her group of DNA matches all tie into! Jackie also shared with Robbi that one of William and Esther Banks’ sons, John, disappeared after finding out that his wife had an affair with one of his brothers, and had a child. The brother was Robert Banks, who also disappeared around the same time in winter 1920.

When Jackie obtained the birth certificate of the illegitimate child, Arthur Banks, she was informed that the same birth had been registered a few weeks previously by John Banks who named himself as the father. Martha Banks then re-registered the birth on February 21, 1920, removed John Banks’ name and didn’t name the father. When Arthur was christened shortly after his birth, Robert Banks was named as the father.

Robbi then added William Banks and Esther Maria Hill to her tree as John Anderson’s parents. Nearly all of her mystery matches then had a ThruLines hint or a common ancestor, and showed that the Barrett/Trevour matches were through the William Banks line. With this information, Robbi felt fairly sure that her John Anderson was really John Banks. Her cousin Alan even had an inherited pocket watch with the name John Banks engraved on the back of it!

Robbi still has some more work to do to fully unravel the mystery, but she has made significant progress in discovering more about her paternal grandfather’s side of the family by reevaluating shared matches and continuing to DO GENEALOGY! 

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  1. chevy l brant

    You and N.T.
    Shared DNA: 1,011 cM across 43 segments
    Unweighted shared DNA: 1,011 cM
    Longest segment: 89 cM

    I am so lost am i his 1-2 cousin or his aunt

    • Your DNA Guide

      Hi Chevy – Based on that amount of shared cM, you have a range of possible relationships, from first cousin, half aunt, great aunt, or even great grandparent. If you can determine the general age difference between you and N.T., then that might help you narrow down which relationship fits best.


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