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.
Thank you for the description, that actually makes it a lot easier to understand.
So how do you go about combining the two?
For example, my great grandfather’s sister’s grandson was on the USS Thresher when it imploded. What would his relation be to me?
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.
Siblings of grandparents are “granties” and “gruncles”
Great grandfather’s sister’s grandson is your second cousin once removed. That guy is the second cousin of one of your parents because they share great grandparents with one of your parents. A grandparent’s sibling is a great aunt or great uncle to you. A great grandparent’s sibling is a great great uncle or great great aunt to you.
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.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