Mitochondrial DNA (MtDNA) is different from other DNA because it is located in the mitochondria, not in the cell nucleus. It is passed from women to all their children, with very infrequent mutations. Men do not pass it on.
I did a Mitochondrial DNA test about a dozen years ago, so I know that Etta Bryna's MtDNA is the haplogroup U1b1. But being a male, I did not pass it to any of my children.
Two of my sisters have no daughters, so they have not passed it on.
Two of my sisters have one daughter each. Those daughters have eight sons between them but no daughters. So they did not pass on the MtDNA.
One sister has two daughters but no grandchildren yet.
So we may have no continuing inheritance of Etta Bryna's MtDNA among my mother's descendants.
My mother's two brothers and one unmarried sister did not pass it on.
My mother's eldest sister gave birth to one daughter and she has one daughter who has one daughter, a teenager. At this stage, this young cousin may be the only one of my grandmother's descendants who can pass this on.
My grandmother had a brother who, being a man, did not pass on his mother's MtDNA.
My grandmother had two sisters who died young, with no children.
My grandmother's older sister in Russia had mostly boys. Of her two daughters who reached adulthood, one had no children and one had only a son.
So Aunt Ethel's teen-aged great-granddaughter may be the only descendant of Etta Bryna who can preserve the U1b1 MtDNA in our known family.
For a woman who had four adult daughters, as Etta Bryna did, I think that is unusual, especially since my mother alone had five daughters. Or maybe it's not unusual at all. (I will look at my other great-grandmothers in a separate post.)