Blood Relations: Theory & Concepts

The questions on blood relations are an integral part of the reasoning or mental ability section of almost all the competitive exams. You will mostly see 2- 3 questions on this in the tests. Sometimes the number increases as the examiner may put a full block of 3 – 4 questions based on relationships. Before we move on to some solved problems on blood relations, let us go through some typical relations and the direct meanings of the same. In most of the questions on blood relations, the statement always gives an indirect reference to the person. Hence, it becomes really important to learn these blood relation tricks.
Blood Relation Chart
Indirect Reference The real relation
Father’s or Mother’s Daughter Sister
Father’s or Mother’s Son Brother
Father’s or Mother’s Sister Aunt
Father’s or Mother’s Brother Uncle
Father’s or Mother’s Mother Grandmother
Father’s or Mother’s Father Grandfather
Daughter’s Husband Son-in-law
Son’s Wife Daughter – in – law
Husband’s or Wife’s Brother Brother – in – law
Husband’s or Wife’s Sister Sister – In – law
Brother’s Daughter Niece
Brother’s Son Nephew
Brother’s Wife Sister-in-law
Sister’s Husband Brother- in- law
Aunt’s or Uncle’s Son or Daughter Cousin
Granddaughter’s or  Grandson’s daughter Great grand daughter
You must go through this blood relation chart in a detailed manner. Do remember that paternal grandfather, paternal grandmother, father, mother, brother, and sister are considered to be blood relatives. Unless mentioned otherwise, all the relations are considered from the father’s side i.e. grandfather will refer to your father’s father and grandmother will refer to your father’s mother unless mentioned otherwise. In statement based relation questions, a technique called backtracking is applied.
Backtracking means starting from the last word & moving backwards. Eg- if Nikhil said, “A is the daughter of the sister of my father’s only son”.
Then we start from the last information: “My father’s only son → Me
Daughter of my sister → “Niece”
Hence A is the niece of  Nikhil.