how are we related?

how are we related?

what is a second cousin? or, a first cousin once removed?

I had my DNA tested over two years ago. Actually, my husband asked my brother to donate his DNA to be tested as a birthday present for me. For the hobby genealogist, it truly was a wonderful gift! After two years of my DNA data residing in a database of others who had their (or their male relatives’) DNA tested residing in the same database, I am meeting more ‘cousins’ than I ever thought possible. (You can learn more about genetic DNA testing here).

I receive emails from people all over the world whose autosomal DNA segments match up to the same segments on my autosomal DNA to varying degrees. The longer the matching segments, the great probability of a closer relationship. For more detail on autosomal DNA and matching segments, 23andMe offers easy to understand information on the process.

After we see there’s a probable relationship, how we determine which common ancestor we share is a matter of looking for common surnames and exploring each other’s family trees. Once we find a shared common ancestor, the next logical question is, “how are we related?”. It can seem complicated!

If you have your family tree documented at, they have a handy tool where you simply click on the person in question and select, View relationship to me. If you don’t, there are many family relationship charts online that you can reference. I confess I find many of them confusing, however I did find one that was easy for me to follow. I hope you think so, too.

table of cosanguinity

Such a serious word, cosanguinity. It simply means blood relation. This is not my chart, so I must give credit to the creator:

Pick a box, any box (except the one labeled ‘Person’, that’s you!). If you want to know what their offspring’s relationship is to you, look at the next box down (unless there isn’t one, but at that point, it’ll be easy to figure it out). The next box down defines the relationship.

how are we related

For instance, go to the box marked ‘Great Grandparents’. To figure out who the children of your great grandparents are in relation to you, move down to the next box, which shows, ‘Great Uncles, Aunts’. You probably knew that, but, who are the children of your great uncle or aunt in relation to you? Your first cousins once removed. So, who is your second cousin? That would be the children of your first cousins once removed. And so on.

Not sure how you’re related to someone? Contact us and we’ll be glad to help!