The grandson of your great grandmother's brother is second cousin to one of your parents, and your second cousin once removed.
There is no word in the English language for a relationship between grandmothers of related grandchildren
There is no relation between you and your grandmother's cousin-in-law's grandson.
Your grandson and your brother's grandson are second cousins to each other.
nothing
a relationship between brothers should be sacred and good....
First cousins
First cousins
Aunt and nephew
Hopefully, women who are grandmothers of the same children are friends, but in western culture they are not otherwise related. They are the mothers of the parents of the children
grandfather grandson.
If your daughter-in-law's grandson is a child from a marriage before she married your son, or after their marriage ended, her grandson is not related to you. If he is a child of the marriage between your son and your daughter-in-law, then he is your great grandson.
Shah Jahan was the grandson of Akbar.