I checked a similar situation in my own tree.

then you'd be second cousins, so I stand corrected. You are correct.


https://en.wikipedia.org/wiki/Cousin

It'll stop a lot of guessing in my family

If the closest common ancestor is a grandparent, you're cousins.
If the closest common ancestor is a great grandparent, you're second cousins.
If you share a common ancestor is a great great grandparent, third cousins.
Etc., etc.

This is from 2012 but it is still relevant.

http://blog.23andme.com/news/announcements/how-many-relatives-do-you-have/

Reply #2 is correct. It all links back to the closest common ancestor.

Your Grandfather's Sister is your Great Aunt. I don't know which parent, but let's say your Mom for the sake of discussion:

- Your Great Aunt would be your Mom's Aunt
- Your Great Aunt's children would be your Mom's First Cousins

OK - hold that thought for a moment.

Let's say You have an Aunt (your Mom's Sister)

- Your Aunt's children would be your First Cousins
- Your First Cousin's Children are your Second Cousins
- Their Children are your Third Cousins...and so on

So when something applies to your parent's generation, it is "once removed"
- So your Mom's First Cousin (your Great Aunt's child) is your First Cousin, Once Removed
- If that Cousin has a child, it would be your Second Cousin, once removed.

- Your Aunt's children would be your First Cousins
- Your First Cousin's Children are your Second Cousins
- Their Children are your Third Cousins...and so on

No, your first cousin's children are your first cousin's once removed.
Their children are your first cousins twice removed.

Last week I got an email from someone who turned out to be my 5th cousin. We share 4th great grandparents.

The degree of cousins is one more than the number of "greats" grandparents that is shared. If you share grandparents, you are first cousins, great grandparents, you are second cousins. "Removed" comes in when you are not on the same generation level. Go back to the nearest common relative from the person on the oldest generation level, count the number of greats in the grandparents, add one to determine the cousin level, then account for the number of levels off as removed.

The father of my fifth cousin is my 4th cousin, once removed. ( from his perspective, we share third great grandparents, 4th cousins, then because I'm not from his generation, once removed. )

His father is my 3rd cousin, twice removed.

His father, 2nd cousin, three times removed.

His father, 1st cousin, 4 times removed.

His father, becomes my 4th great uncle, the sibling of my 3rd great grandfather.


What seems weird to me is their is no "grand" in uncles/aunts. My grandparents siblings are my great aunt/uncle. No grands. Also no collective/ gender neutral name for aunts/uncles.

There is no such thing unless it is a great grand aunt/uncle.

I was corrected on this by Holy Cross Cemetery in Colma, CA not knowing that there is such a thing as a "great aunt/uncle" so to speak.

I recently found a half cousin. His grandmother was my mother's 1/2 aunt!

Great aunt/uncle is a thing, it is what Family Tree Maker software uses.

Holy Cross Cemetery may prefer Grand aunt/uncle, but they are not really the authority on heredity by any measure.

My mother had a half aunt, she died childless, but when I "created" a grandchild for her, FTM said that would be my half second cousin.

You are 1st cousins if your closest common relatives are grandparents. You are 2nd cousins if your closest common relatives are great grand parents. If you share only one great grandparent, which would be the case in the example you cite, it is half second cousin. Your mother is a half cousin with one of the parents of the person you are talking about.