Your brother is your grandson's great uncle, and your grandson is your borther's great nephew.
Some people would also say grand nephew and grand uncle.
Your sisters grandson would be your grandnephew.
Yes, you are related to your brother-in-law's grandson. Your brother-in-law's grandson would be your nephew once removed. This means that you are not directly related by blood, but you share a family connection through your brother-in-law's family.
The relationship between the families of inlaws is similar to the relation ship with their family members. For example The relationship of my brother in law(sister's husband) and my another brother in law (wife's brother) will be simmilar to those relation ships with their brother's family.
Brother-in-law
Your great-aunt
Your great grandfather's brother is your great great uncle.
second cousin
Your aunt's great grandson is your first cousin twice removed.
She would be your niece. and you would be her uncle.
Your brother's wife is your sister-in-law. The English language has no relationship term for the brother of your sister-in-law. He is not considered to be related toyou, although he is your brother's brother-in-law.
Many genealogy programs include a feature that calculates relationships between family members. The relationship between a grandmother's brother and a her grandchild is "grand uncle" or "great uncle." Learn more at 23andme.com.
Your grandmother's brother is your children's great-granduncle (or great great uncle). They are his great-grandnieces and great-grandnephews.