That man was Robert Ivan Nichols.
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## Third-Cousin Confirmation: How the Tree Converged
The genealogical process that led from distant GEDmatch matches to the specific identification of Robert Ivan Nichols involved the kind of systematic family tree construction that genetic genealogists routinely perform, applied to a degraded profile that required particular care and iteration.
The process begins with the DNA matches themselves. When a profile is uploaded to GEDmatch, the system compares it against all other profiles in the database and returns a list of people who share detectable amounts of genetic material, ranked by the estimated closeness of the relationship. For the Chandler profile, the closest matches available were individuals estimated to be third cousins or more distant — people who shared a great-great-grandparent or more remote ancestor with the deceased.
Third cousins share approximately one quarter of one percent of their DNA. The detection of genuine third-cousin relationships in a degraded sample requires careful statistical analysis to distinguish from false positives. The DNA Doe Project’s methods, adapted to the low-quality Chandler profile, were able to identify genuine third-cousin level matches with sufficient confidence to use them as starting points.
For each matched individual, the genealogists traced their family tree backward — through parents, grandparents, great-grandparents, and great-great-grandparents — trying to identify the common ancestors that the deceased and the match had shared. This is work that combines genetic analysis with traditional genealogical research: searching birth, marriage, and death records; census records; military service records; obituaries; and other documentary sources to reconstruct the family structure of people who lived and died in the nineteenth and early twentieth centuries.