What Is Brother Son Called?

nephew. a son of your brother or sister, or a son of your husband's or wife's brother or sister. Their daughter is called your niece.

What do we call my brother's son?

Nephew Definition & Meaning - Merriam-Webster.

What is your brother's son to you?

A nephew is the son of your sibling. This makes you the aunt or uncle of that nephew. While a mom, dad, sister, and brother are members of an immediate family, a nephew is part of your extended family because he's the son of a sibling.