If there’s a time period where you can’t find an ancestor or a time after which you cannot find an ancestor or relative, as yourself:
What was changing at that point in time?
That change could be why your cannot find your ancestor. Has the family structure of your ancestor just changed (spouse, death of a family member, etc.)? Had your relative’s children just grown up? Was the political environment changing? Was the economy changing and their occupation was not as in demand as it was before? Were there increasing economic opportunities in other areas? Are there county boundaries that are changing? Were their neighbors moving away and they decided to follow them?
Most of us know that life is about constant change. It was for our ancestors as well. Think about what might have been changing for your ancestor during those times that she cannot be found. Your answer could be in that change.
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