Reading the account of my pioneer family history inspired me to try and sort out second and third cousins and cousins once or twice removed (I know I’ve looked this up many times before but I think this time I actually got it to stick in my head), and I thought I’d share some of my newly re-found knowledge. First off, I came across this handy though somewhat brain-twisting kinship chart:
So, numbered cousins are always in the same generation as you (though of course they might be substantially older or younger), removed cousins go up or down in generations. Got it. Because of the long generations in my family I’m thinking all of my second and third cousins are a lot older than I am, however, and I’d have to get down to second or third cousins twice removed to find someone actually my age.
What I found really interesting is that the children of your first cousins, (your first cousins once removed), have the same relationship to you as your grandparents’ nieces and nephews (these are also your first cousins once removed). I had no idea cousins worked like that but it actually makes sense: you are on opposite sides of the same relationship. For example, in the first instance, the grandfather of your first cousins once removed is your uncle, in the second instance your grandfather is the uncle of your first cousins once removed. Kind of mind-bending but interesting. This means I actually have lots of first cousins (once removed) that I don’t know the first thing about.
It also made me realize how strange it is to quantify these relationships. Not only do I not know any of these people and could have interacted with their descendants (my second cousins several times removed etc) many times in my life already for all I know, but looking farther out on the chart gives a whole new perspective on the idea that everyone is related by the sixth cousin. To be a sixth cousin you only need to have a great-great-great-great-great-grandparent in common. Everyone, or at least most people, will have 126 of these 5th great grandparents and somewhere between 23,000 and 174,000 sixth cousins, depending on whether a two child or six child family size is used as the model. If you go to eighth cousins that’s half a million people. Obviously we aren’t all related by the sixth cousin, but after the first cousin it does seem like the term gets a bit meaningless…