How We Are Related
When I was growing up, I knew my cousins were the children of my Aunts and Uncles. What I didn’t know was how those relationships worked. When my cousin Lynn had her first child, my family and I wrongly assumed that this must be my second cousin.
After beginning genealogy research, I had a computer program that would tell me kinships. I then learned that who I considered my second cousin, was really my first cousin once-removed.
I thought I would share with you what I’ve learned about kinships. I always try to think of who our common ancestor is and work from there.
First cousins (or just cousins) have the same grandparents.
Second cousins have the same great-grandparents.
Third cousins have the same great-great-grandparents, etc.
The “once-removed” tag is really shortened meaning one generation removed.
So the grandchild of your first cousin is your first cousin twice-removed since he/she is two generations removed from you and your first cousin.
When visiting Zelhelm, Netherlands in 1997, my family and I met distant relatives, Henk Walvoort and his father Hendrik. Henk had also researched his family tree and while comparing notes, we found a common ancestor, Salomon Walvoort (1778-1848) and his wife Maria Elisabeth Klumpenhouwer (1781-1840).
I then worked my way down each tree one generation at a time, being careful to do so on both of our trees at the same time keeping the same number of generations on each page. When I reached Henk’s name on his tree, I had only reached my grandfather (Randall Henry Walvoord) on my tree.
There were five generations from Henk and my late grandfather to their common ancestor making them 4th cousins.
You may be asking yourself, “If there are five generations to their common ancestor, why aren’t they 5th cousins?” The first generation after Salomon Walvoort and Maria Elisabeth Klumpenhouwer aren’t cousins they’re siblings. In this example, brothers.
My dad and Henk are 4th cousins once-removed. That means Henk and I are 4th cousins twice-removed.
But what about Henk’s father Hendrik Jan Johan Walvoort? What is our kinship?
Hendrik is one generation closer to our common ancestor so he would be a third cousin to, not my grandfather, but to my great-grandfather (John Garrett Walvoord). So that means Henk’s father Hendrik and my dad are 3rd cousins twice removed and Hendrik and I are 3rd cousins 3 times removed. Clear as mud?
While it may seem unusual in today’s American culture, in the Dutch culture of days past, cousins marrying each other was quite common. My great aunt Louise Walvoord suggested in her diaries that cousins would marry cousins to keep the family wealth intact.
A double cousinship occurs only when a set of siblings marries another set of siblings and both have children. In the case, of Jan Derk ”J.D.” Walvoord and his wife (and double-cousin) Johanna Gesina Walvoord, are the offspring of two sisters who married two brothers. It could also occur when a brother and sister marry a sister and brother (in this case the maiden names would differ from her cousin/husband).
Double cousins actually share the same gene pool as siblings. They share all four of the same grandparents. Most cousins share only one set of grandparents.