I do not know about the Roberts family in Kentucky, but my Roberts ancestors in the Bahamas liked to marry their cousins and family names were often repeated. It is hard to get a complete picture even with ALL available records. My great × 2 grandmother Matilda Roberts, daughter of John Roberts, Jr. married her uncle William Roberts, Sr. My Family Tree DNA results are very skewed with so much inbreeding, making 5th cousins on the family tree genetically like 2nd or 3rd cousins. Even my 5th cousin Peter J. Roberts, head of the Bahamas Project is not sure who's who. Ben Roberts, for example, is my predicted 2nd cousin with 394 centimorgans, yet he is not on my family tree. It's a wonder that we do not all have congenital abnormalities.