Well that would depend on if you were the biological grandfather. If so then the grandchild is also your grandchild. If the child was born to a child of your ex-wife and not fathered by you then they are no relation to you and you would call them by their name.
auntie .
second cousin
Your uncle's grandchild would be your second cousin because his grown son or daughter would be your first cousin.
Your brother's great grandchild is your great great nephew (if a boy) or great great niece (if a girl). You are their great great aunt.
Great aunt or great uncle depending on your gender.
Your first cousin's grandchild is your first cousin twice removed
it depends on what you allow but da is short for dad
Biologically, the grandchild is a step-grandchild to the grandparent that had no children. In matters of the heart, however, the grandchild is whatever the grandparent feels it is.
If a grandchild is not a sibling, they can be referred to as a cousin, if they share a set of grandparents with another child. Alternatively, they can simply be identified by their relationship to the grandparent, such as “grandson” or “granddaughter.” In familial contexts, terms like "nephew" or "niece" could also apply if the grandchild is the child of a sibling of the individual in question.
The plural of grandchild is grandchildren.
Answer: We would call Her your "Great Grandmother" ~ 1)your Moma's Mother would be your Grandma or GrandMother. 2) your Grandmother's Mother is your Great-Grandma or Great-Grandmother .. {1) you are your Mother's Child. 2) You are your Grandmother's Grandchild , and you are the Great Grandchild of your Great Grandmother....
The grandchild of your grandmother's first cousin is your third cousin. The grandchild of your grandmother's second cousin is your fourth cousin. The grandchild of your grandmother's third cousin is your fifth cousin.