I don’t expect to get one definite answer here, but Google can’t give me one either. Some websites say they’re your second cousin, and others say they’re your first cousin once removed. I’m trying to figure out some family tree stuff so I need to know the difference between the (groups of) terms.

  • entropicdrift@lemmy.sdf.org
    12·
    1 month ago

    For example, my great grandfather’s sister’s grandson was on the USS Thresher when it imploded. What would his relation be to me?

    So your first common ancestors are your great great grandparents, so that’s third cousin, and they’re a generation older than you, so once removed. Third cousin once removed. EDIT: This was incorrect, it’s second cousin once removed since that person would be OP’s parent’s second cousin. See the replies below.

    On that note, what do you call your grandparent’s sibling, vs your great grandparent’s sibling, and so on? Again, Google isn’t being very helpful here.

    Grandparents’ siblings are you great aunts/great uncles, additional generations back you add more greats, so great grandparents’ siblings are your great great aunt/uncle. After a while people say “twice great” etc

    • bobagem@sh.itjust.works
      3·
      1 month ago

      So your first common ancestors are your great great grandparents, so that’s third cousin, and they’re a generation older than you, so once removed. Third cousin once removed.

      I believe that the answer is second cousin once removed.

      I believe you need to count the distance to the common ancestor from the older generation of the two people being related.

      I agree that the first common ancestor is OP’s great-great-grandparent. But only OP’s relation’s great-grandparent. So OP’s parent and OP’s relation are second cousins.

      Then the removed takes you down the tree from OP’s parent to OP.

      • entropicdrift@lemmy.sdf.org
        2·
        1 month ago

        Ah, you’re completely right.

        If that person had a kid it’d be your third cousin, but since that person is OP’s parents’ second cousin, they are OP’s second cousin once removed.