When two brothers marry two sisters, the children of those two couples are sometimes called double cousins. In other words, each cousin is related to the other cousins twice, through both sides of their family.
While I've been writing about the roots of my mother-in-law's third great-grandfather, Mathias Ambrose, in the background, I've had a second mission: to place all his descendants in my family tree so I can identify all the family's DNA matches in the right branch of the tree. Of course, that eventually turns into a whack-a-mole game. For each DNA cousin I place in the tree, another one pops up to take its place among the unidentified.
Undaunted, I'll continue the process for the remainder of this month, with one twist: I'd like to focus on the descendants of those double cousins who called Mathias Ambrose their maternal grandfather. That means we'll take a closer look at the children of Elizabeth and Susannah Ambrose, the sisters who married two Flowers brothers in Pennsylvania and then moved to Perry County, Ohio.
My curiosity in this process is to see how the DNA relationship estimates match up to the actual relationships according to documentation. While double cousin situations do not exactly confer endogamy status, my mother-in-law's family is the one with so many multiple relationships that I've come to call that connection "endogamy lite." It goes just a little bit beyond pedigree collapse.
For the remainder of this week, we'll use the opportunity to take a closer look at the family of Elizabeth and Joseph Flowers, and then the family of her younger sister Susannah and husband Henry Flowers.
Double-first cousins are great. My grandmother's brother married my grandfather's sister, around the turn of the century. Each couple raised seven children on neighboring farms - it was almost like 14 siblings. I find that the descendants of my mother's double-first cousins have a "boosted" DNA relationship to me, the cM coming up about half-way between my "normal" first cousins and second cousins.
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