Blood relations questions ask you to decode the family relationship between two people after a chain of clues — sometimes straightforward, sometimes deliberately scrambled through double negatives, coded symbols, or conversations where someone says "her brother's father is my grandfather's only son." The trap is not the logic — it is the language.
Think of it like this: every human being occupies exactly one node on a family tree. That tree has three axes you need to care about:
The analogy: imagine a village register (गाँव की खाता-बही) where every family entry has a position. All these questions are asking you to read that register correctly. The moment you draw the tree and place each person at the right node, the answer becomes arithmetic, not guesswork.
What makes this topic specific to IBPS RRB PO is the volume of multi-step chain questions — five to eight people, multiple clues, and you must trace the path from Person A to Person B cleanly. Rural banking officers deal with joint family accounts, nominee registrations, and inheritance documentation daily, so the examiners are testing whether you can untangle family structures under pressure.
Two question types dominate:
The second type looks harder but is actually faster if you have the right method, which you will by the end of this page.
Before anything else, internalize the standard kinship titles. Do not rely on vague cultural memory — the exam uses English terms precisely.
| Relation Chain | Title | |---|---| | Father's / Mother's father | Grandfather | | Father's / Mother's mother | Grandmother | | Father's / Mother's brother | Uncle | | Father's / Mother's sister | Aunt | | Uncle's / Aunt's child | Cousin | | Sibling's son | Nephew | | Sibling's daughter | Niece | | Spouse's brother | Brother-in-law | | Spouse's sister | Sister-in-law | | Son's / Daughter's child | Grandchild |
Draw a tree. This is non-negotiable. Every second you spend "holding the chain in your head" is a second wasted. Use these conventions consistently:
M = male, Circle or F = female= symbol between two names = married coupleStep-by-step for multi-statement puzzles:
Here's the generation-counting rule: if Person A is n steps above Person B, and they share a common ancestor at level k, the relationship is determined by both n and k. In practice, for IBPS RRB PO questions, the chains rarely go beyond 3 generations, so this stays manageable.
For sentences like "Her brother's father is the only son of my grandfather," work backwards by substituting simpler equivalents at each step:
So: her father = my father → she is my sibling.
The key substitutions to memorize:
| Phrase | Simplifies to | |---|---| | X's mother's husband | X's father | | X's father's wife | X's mother | | X's brother's father | X's father | | X's sister's mother | X's mother | | X's father's father | X's paternal grandfather | | X's parent's only son | X's father (if "only") or X's father/uncle | | X's parent's only daughter | X's mother (if "only") or X's mother/aunt |
The word "only" is a gift — "the only son of my grandfather" means exactly one male child of that grandfather, which eliminates uncle-type ambiguity.
When the tree has 3+ generations, assign level numbers:
Place every person at the correct level as you build the tree. Two people at the same level are potential siblings or cousins (depending on which branch they fall on). Two people one level apart are potential parent-child or aunt/uncle-niece/nephew pairs. This catches errors before you commit to a wrong answer.
Many IBPS RRB PO questions use gender-neutral names (K, M, N, P, Q) or Indian names that don't immediately signal gender. Look for:
If a person's gender remains ambiguous after all clues, the question will typically have an answer that doesn't depend on resolving it — or the answer choices will tell you (if the correct option is "sister," you know the gender of that person).
Some questions code relationships with symbols: A + B means A is father of B; A - B means A is mother of B; A × B means A is brother of B; A ÷ B means A is wife of B. The approach is identical — translate the code back into plain relationships and build the tree. Do not try to decode the entire expression mentally; write each link.
Whenever a clue says "X's [brother/sister]'s [father/mother]", immediately collapse it: a sibling and the self share the same parents, so "X's brother's mother" = "X's mother." This turns a 3-step chain into a 1-step chain.
Micro-example: "Her brother's father is my grandfather's only son." Without the trick: 4 logical steps, ~40 seconds. With the trick: "brother's father = father" and "grandfather's only son = father" → her father = my father → siblings. Time: under 10 seconds. Step count drops from 4 to 2.
Assign numbers to generations the moment you start drawing. Write -2 next to grandparent nodes, -1 next to parent nodes, 0 next to the self/anchor, +1 next to children. When the question asks the relationship between two people, look at their level difference and branch separation.
Same level, same branch = siblings. Same level, different branch (one step removed) = cousins. One level apart, same branch = parent/child. One level apart, different branch = uncle/aunt — nephew/niece.
Without numbering: confuse uncle with grandfather in a 4-generation tree, lose 2 marks. With numbering: the level difference (2 vs 1) catches the error in 3 seconds.
When a question says "the only son of X" or "the only daughter of X," it eliminates every alternative sibling for that person. This collapses ambiguity instantly.
Example: "The only son of my grandfather" = my father (not uncle, not any cousin). Without "only," you'd have to consider: could be father OR uncle — two options. With "only," there is exactly one candidate. Reduces a 30-second deliberation to a 5-second confirmation.
For "looking at a portrait" or "pointing to someone" questions, always test whether "my father's son" = the speaker himself. In most IBPS questions the speaker has no mentioned siblings, so "my father's son = me." This instantly simplifies: "his mother is the wife of my father's son" → "his mother is my wife" → the person in the portrait is my son.
Standard approach (treating "father's son" as possibly a brother): trace two branches, compare, ~45 seconds. Self-reference test: substitute self first, check for consistency, done in ~12 seconds.
When you see two people who are both described as children of the same parent (or siblings of the same person), they are in the same cluster. Mark them with a bracket. Then any question about one person's relationship to the other's child automatically becomes aunt/uncle → nephew/niece.
In an 8-person puzzle, identifying 3 people as one sibling cluster and 2 as another reduces the tree from 8 unknowns to 2 cluster units. Cuts tree-building time from ~3 minutes to ~90 seconds for complex puzzles.
Use this decision tree in the exam hall:
Step 1 — Identify question type Single-sentence conversation/pointing type? → Go to Method 2 (Reverse Substitution Chain). Multi-statement puzzle with 5+ people? → Go to Method 1 (Node-and-Arrow Tree).
Step 2 — Spot gender locks Scan all clues for explicit gender words (mother, father, sister, brother, wife, husband, son, daughter). Underline them. These are fixed points — build around them.
Step 3 — Spot "only" keywords If "only son" or "only daughter" appears, immediately collapse alternatives. This is your biggest time-saver in conversation-type questions.
Step 4 — Apply the Parent-Sibling Collapse Simplify "sibling's parent" to just "parent" before building the tree. Reduce chain length first, then draw.
Step 5 — Count levels, assign title Trace the path between the two people the question asks about. Count the generation gap. Cross-reference branch (same family line or different). Apply the correct title based on gender.
If confused by answer choices: eliminate by gender first — wrong-gender options go out immediately. Then eliminate by generation — a grandparent option cannot be correct if both people are on the same level.
Aim: single-sentence questions in under 20 seconds; 6-8 person puzzles in under 2.5 minutes.
Why this question: Tests the Parent-Sibling Collapse in a pure conversation-type format — the exact structure that appears most often in IBPS RRB PO.
Solving path: "N's mother's husband" = N's father. "N's father's sister" = N's aunt. If this same person is M's aunt, then M and N share an aunt. Shared aunt at parent level = M and N are cousins.
Why this question: A classic 6-person chain puzzle — tests whether you can build a tree correctly and then answer a cross-generation question (S to P, which spans 2 levels).
Solving path: T is father of M; S is wife of T → S and T are a couple, S is mother of M. M is sister of K; K is brother of N → M, K, N are all siblings (same generation, same parents T and S). P is daughter of N → P is S and T's grandchild. S is P's grandmother.
Why this question: An 8-person puzzle where the connection between two families (T-S side and U-R side) is hidden in the clue about R being S's brother. Catches students who build two separate trees instead of one.
Solving path: T is mother of P and S (S is daughter of T). U is father of R and V (R is brother of S). Since R is S's brother and S is T's daughter, T and U must be the parents of both R and S — they are a married couple. P is T and U's child; V is T and U's child. But P and V are children of different parents within the combined tree: P's father is Q (married to T's sibling line? — re-read). Actually: T is mother of P (so Q is P's father, W is Q's wife meaning W=T, so T=W). U is father of R and V, separate family. R is brother of S, S is daughter of T(=W). So T and U are the parents of S and R — which means T married both Q and U? No — trace carefully: T is mother of P and S; U is father of R and V; R is brother of S; this means S has two parents — T (mother) and U (father). So T and U are married. P is T's son, V is U's son → P and V are cousins (P's mother T and V's father U are a couple, but P's father is Q — meaning Q is T's first husband or Q=U). The explanation confirms T and U are married, making P and V cousins.
Why this question: Tests the "only son" unlock plus a two-family cousin chain — a pattern repeated every year in IBPS RRB PO.
Solving path: "The only son of my grandfather" = the man's father. "Her brother's father" = her father (Parent-Sibling Collapse). Her father = man's father → they are siblings. The man is the woman's brother.
Why this question: The portrait/pointing self-reference type — tests whether you apply the self-reference test correctly for "my father's son."
Solving path: "My father's son" = Rohit himself (no brother mentioned, so self-reference applies). "His mother is the wife of Rohit" → Rohit's wife is the mother of the person in the portrait → the person is Rohit's son.
Forgetting to assign gender after placing a node. You build the tree correctly but then say "uncle" when the clue said "aunt." Lock the gender label at the moment you write the name — never leave a node gender-ambiguous if a clue resolves it.
Treating "father's son" as always someone else. In most IBPS questions, "my father's son" = the speaker (self-reference), unless the question explicitly introduces a brother. Applying the "brother" interpretation by default leads to a wrong branch in portrait questions.
Not collapsing the sibling-parent chain. Writing "brother's mother" as a separate person from "mother" creates a phantom extra node in your tree and makes a 5-person tree look like a 7-person one. Always collapse X's sibling's parent → X's parent before drawing.
Mixing up maternal and paternal lines for cousins. Both your mother's brother's child and your father's sister's child are your cousins — same title, different branches. The exam usually doesn't ask you to distinguish maternal from paternal cousins, but when building a tree, mixing the two branches wrongly can put a cousin node in the wrong position and give you the wrong final answer.
Ignoring the spouse link. In multi-person puzzles, the married couple is the bridge between two family lines. Students often skip writing the horizontal marriage line, causing the two branches to float disconnected. Always explicitly draw the marriage link — it is the source of the cousin relationship in most IBPS puzzles.
Answering the gender wrong when both sibling options are possible. If the question asks "how is M related to N" and the clues don't resolve M's gender, the answer might be "brother or sister." If the options say "sibling," that is the answer. Don't guess a gendered answer when the data doesn't support it.