6.1 Blood Relations

Why This Matters

Blood relations questions appear in 3 to 5 of the 30 Reasoning marks on the RRB Group D CBT, and they are among the most reliable scorers once the vocabulary is fixed. They test whether you can translate a chain of family statements into a kinship diagram under exam pressure. Two formats dominate: narrative pointing puzzles ("Pointing to a photograph, Reena said…") and symbol-coded relations ("A + B means A is the father of B"). Both reward the same skill — anchoring the speaker's reference point and drawing a generation tree.

Core Terminology

Paternal means the father's side (paternal uncle, paternal aunt, paternal grandfather); maternal means the mother's side. In Indian English, "cousin" is gender-neutral, so RRB questions usually specify "father's brother's son" rather than the bare word. Siblings share parents; half-siblings share exactly one. An in-law is a relation through marriage, not blood. The table below consolidates the relationships most often used in RRB statements.

You do not need the Hindi terms for the CBT itself, but many setters embed them inside statements, so recognizing them prevents a stall mid-question.

The Point-to-Self Method

For "pointing to" questions, run three steps:

1. Identify the speaker — the person pointing or saying "my father."
2. Convert every pronoun ("my," "his," "her") to the speaker's frame.
3. Walk back to the target person, one link at a time.

Worked example: "Pointing to a man, Reena said, 'His mother is the only daughter of my mother.' How is the man related to Reena?"

• Speaker: Reena.
• "His mother" = the man's mother.
• "Only daughter of my mother" = Reena's mother has exactly one daughter, which is Reena.
• So the man's mother is Reena. The man is Reena's son.

Symbol-Coded Relations

RRB typically fixes the symbols in a key:

• A + B means A is the father of B.
• A − B means A is the brother of B.
• A × B means A is the wife of B.
• A ÷ B means A is the sister of B.

To decode a string such as P × Q − R + S, read left to right and build the tree step by step, labeling both gender and direction at each link:

1. P × Q — P is the wife of Q, so P is female and Q is male.
2. Q − R — Q is the brother of R, so R is a sibling of Q (gender not yet fixed).
3. R + S — R is the father of S, so R is male and S is a child of R.

Now relate P to S: P is the wife of Q. Q is the brother of R. R is the father of S. So Q is the uncle of S (brother of S's father), and P, as Q's wife, is S's aunt by marriage.

A Second Worked Example

"He is the son of the son of my father." Speaker is female. How is the man related to the speaker?

• "Son of my father" — the speaker is female, so her father's son is her brother.
• "Son of [my brother]" is the brother's son, which is the speaker's nephew.

Handling Long Chains

When a statement gives three or more links ("the son of the brother of the father of my sister"), break it from the inside out. Start with the innermost possessive ("my sister") and resolve outward. Each step collapses the chain by one link. After three or four collapses, you arrive at a single kinship label. Drawing a small generation tree as you go — even on scratch paper — catches the gender and direction errors that lose marks.

Worked example: "A is the father of B, B is the brother of C, C is the father of D." How is A related to D?

• A → B (father of): A is one generation above B.
• B → C (brother of): B and C are siblings, so A is also the father of C.
• C → D (father of): C is one generation above D.
• A is two generations above D — A is D's grandfather.

Reverse Relations Quick Reference

When the question asks "How is X related to Y," invert the relation Y has to X.

Exam Traps

• "Only daughter" does not mean "only child" — the parent may also have sons. Count sons separately.
• "Daughter of the only son of my grandfather" reduces to "daughter of my father," which is "me or my sister."
• Gender-neutral words ("child," "person," "student") keep options open until evidence fixes gender. Never assume male by default; the answer often hinges on the one piece of evidence that fixes gender.