Well, your cousin's brother is also your cousin, and a cousin's son is also your cousin.
No relation.
Cousin brother
fourth cousin
Your daughter's grandfather's brother's son is her mother's or father's first cousin and her first cousin, once removed.
Your granpa's brother's son's son is your 2nd cousin.
Your grandfather's half brother is your great uncle.
He would be your first cousin once removed.
There really is no relationship named or defined as cousin-in-law. If you and the son of this individual do not share a common ancestor you are not related at all.
Your mother's cousin's son is your second cousin.
Your first cousin's nephew is the son of your first cousin's sister or brother. That sister or brother is also your first cousin, and the son is your first cousin, once removed. So your first cousin's nephew is your first cousin, once removed. Similarly, your second cousin's nephew is your second cousin, once removed.
It's your second cousin (:
The son of your mother's third cousin is your fourth cousin.
Your father's brother's son is your cousin or first cousin.