Calculating Cousins
We all know that the offspring of your parent’s sibling is your first cousin. What do you call your first cousin’s child? The proper name would not be your second cousin but rather your first cousin once removed, and their child would be your first cousin three times removed.
Your second cousin is your grandparent’s siblings grandchild. That second cousin’s child is your second cousin once removed, his or her child would be your second cousin twice removed and so on.
Your third cousin is your great grandparent’s brother’s or sister’s great grandchild, etc.