Blood relation - Most of us are often confused when it comes to what to call which relative what. It is important to understand these thoroughly when tackling general blood relation problems in various competitive exams like IBPS, SSC, SBI, RRB, ICET and others. We need to understand who is an uncle, aunt, cousin, grandmother, grandfather etc. We need to understand the difference between ‘maternal’ and ‘paternal’. Related through the mother's side of the family is known as 'Maternal'. Related through the father's side of the family is known as 'Paternal'. For the both male and female siblings, children of siblings are nieces and nephews, where girl child is niece and boy child is nephew. The word in - law is used to express relations which you get only after marriage or when a sibling gets married. But in the case of father - in - law and mother - in - law, you must be the one to marry.