Blood Relations

Overview

Blood Relations appears about 1.8 times per paper across the last four AFCAT solved papers, placing it in the high yield band of Reasoning and Aptitude.

Blood-relations items in AFCAT carry roughly 1.75 marks per paper — about two questions out of the 25–30 in the Reasoning and Military Aptitude Test block. With +3 for a correct answer and −1 for a wrong one, locking both of them adds six marks; misreading a single pronoun and choosing the wrong cousin-versus-niece option costs four marks of swing compared with a clean solve. That is one rank-bracket on a competitive cut-off.

The defining feature of AFCAT blood-relation items is that the verbal description is deliberately compact. A puzzle gives you three or four sentences — sometimes a single long sentence — and asks for one specific relation. The trap is psychological: the temptation to read the sentence linearly and answer from memory of the words, instead of translating each clause into a small picture and reading the answer off the picture. Candidates who solve in their heads get blood-relations wrong roughly half the time; candidates who draw a six-line family tree get them right roughly nine times out of ten. This page builds the drawing reflex, the gender-tracking discipline, the full three-generation vocabulary, and the trap-pattern catalogue you need to convert blood-relations from a coin-flip into a guaranteed mark.

Why blood relations rewards systematic notation

Blood-relations puzzles look like reading comprehension. They are not. They are graph problems disguised as English sentences, and the only reliable way to solve a graph problem is to draw the graph. The verbal description gives you nodes (people) and edges (parent-child, marriage, sibling) one at a time; the question asks you to read off a path between two nodes. If the graph lives only in your head, you will lose track of which direction an edge runs or whose gender is fixed by which clue, and you will produce a confident wrong answer.

The cost of this is asymmetric. A solved-in-the-head approach takes 25 seconds and produces a correct answer roughly half the time on three-generation items and roughly a third of the time on items involving in-laws or cousins. A draw-the-tree approach takes 50 seconds and produces a correct answer roughly nine times in ten. Over two items per paper, the expected marks are: head-method 2 × (0.5 × 3 + 0.5 × −1) = 2 marks; tree-method 2 × (0.9 × 3 + 0.1 × −1) = 5.2 marks. The tree is worth three marks per paper before any time you save by not having to re-read the prompt.

The other benefit of notation is that it forces you to commit gender. Every name in a blood-relations puzzle is either male or female, and many puzzles depend on knowing which. If you do not mark M or F next to each name as you read, you will reach the question and discover you do not remember whether the speaker called the third character 'he' or 'she'. The tree forces the commitment. Build the discipline now: every name gets a gender symbol before any edge gets drawn.

The four-step method

Every AFCAT blood-relations item yields to the same four-step routine. Practise it on twenty puzzles until the steps become automatic; then in the exam you will execute them without conscious thought and finish each item in under sixty seconds.

1. Identify the speaker. Find the pronoun that anchors the puzzle — 'I', 'my', 'me' — and circle the speaker's name (or write SPEAKER if anonymous). Every relation in the puzzle is stated relative to this anchor, and every pronoun ('his', 'her', 'their') must trace back to either the speaker or a previously-named character.
2. Track gender for every named person. Before you draw any edge, list each name and write M or F next to it. Use the explicit gender from the sentence ('he is the husband of', 'she is the mother of'), or infer from a relation that fixes it ('A is the father of B' implies A is M). If a name's gender is genuinely ambiguous, leave it as a question mark — the puzzle will resolve it, or the question will not require it.
3. Build the family tree step by step, one relation at a time. Use the standard symbols (next section). Add one relation per sentence; if a sentence contains two relations, add them as two separate edges. Never skip ahead. The tree should grow visibly on the page in front of you.
4. Read the answer off the tree. Trace the path from the asking node to the target node and name the relation in the standard vocabulary. If the path is short (one or two edges), the answer is direct (mother, son, husband). If the path is three edges or more, walk the path slowly and name each step.

Family-tree notation system

You do not need elaborate diagrams. A standard, compact notation drawn the same way every time means you can re-read your own tree at a glance after twenty seconds. Use these symbols:

Lay the tree out vertically with generations stacked top-to-bottom. Older generation at top, younger at bottom. Put marriage partners side by side; put siblings on the same horizontal line linked by the sibling dash. The vertical position alone tells you the generation, which is what most questions actually test.

Worked layout. Suppose the puzzle says: 'A is the father of B. B is the mother of C. D is the husband of B.' You draw three rows. Top row: A (M). Middle row: D (M) = B (F). Bottom row: C (?). The vertical line drops from the D=B couple to C. Now if the puzzle asks 'how is A related to C', you read up the tree: C's parent is B; B's parent is A; A is two steps up from C and is male, so A is C's maternal grandfather. The arithmetic is replaced by a glance at the page.

Three-generation relations grid

You cannot afford to derive every relation on the fly. The thirty common relations across three generations should be reflex-level recall, so that when you have a tree drawn and need to name a path, the right word arrives in one second. The full grid below is the working vocabulary for AFCAT blood-relations.

The three rows you must drill hardest are the in-law set (brother-in-law, sister-in-law and the parent-in-laws), because AFCAT items use them in chained form — 'my husband's sister's son' resolves to 'my nephew through marriage' which in everyday English is just a nephew. The shortcut: walk the tree, name the destination by gender and generation, and ignore the by-marriage qualifier unless the question asks for it explicitly.

Pointing-statement puzzles

The single most common AFCAT blood-relations format opens with the phrase 'Pointing to a photograph' (or 'pointing to a man / woman / girl / boy'). The speaker is named or anonymous, the pointed-at person is the target of the question, and a chain of relations connects them.

Method for pointing-statement puzzles

1. Mark the speaker as the anchor. Their gender is given by the sentence ('a man says', 'a woman says') or by a pronoun later in the puzzle.
2. Mark the pointed-at person as the target. Their gender is given by the noun ('a man', 'a girl', 'a photograph of a woman').
3. Translate the chain into edges. Each clause like 'the only son of my grandfather' is a single edge or a short two-edge path. Draw it and label it.
4. Read the final edge between target and speaker off the tree.

Common phrasings and what they resolve to

The phrase 'only son' and 'only daughter' are the linchpin of most pointing puzzles, because they collapse a branching tree into a single line. Always circle the word 'only' when you see it.

Worked example. Pointing to a photograph, a man says, 'She is the daughter of the only son of my grandfather.' Speaker is male and the anchor. 'My grandfather' is one step up from my father. 'Only son of my grandfather' — only means the path is forced; the grandfather has just one son, who must be my father. 'Daughter of my father' is my sister. Answer: sister.

Reverse-tracking puzzles

A second common format flips the direction. Instead of 'A is X to B; what is A to C?', the puzzle asks 'If A is the brother of B's son, then A is whose nephew?' — you have to work out the relation from A to some implied third party.

Method for reverse-tracking

1. Draw the explicit relation first. 'A is the brother of B's son' — draw B with a child below, then draw a sibling line from that child to A. A and B's son are both male (because brother), and they share B as a parent. So A is also B's son.
2. Identify the implied target. The question asks 'A is whose nephew' — so find a person of whom A would be a nephew. A nephew is a brother's son or a sister's son. So we are looking for a sibling of B (a brother or sister of B), and A would be that sibling's nephew.
3. Express the answer in terms of B's relations. A is the nephew of B's brother and B's sister. If the puzzle gives names, name them; if not, state 'B's brother or B's sister'.

Worked example. If P is the daughter of Q's son, and Q is the father of R, then how is P related to R? Draw: Q (M) → son (M) → P (F); Q (M) → R (?). The two children of Q are 'son' (unnamed) and R. P is the son's daughter. R is Q's child, the son's sibling. So P is R's niece (if R is female, niece; if R is male, niece equally — niece is the gender-correct word because P is female; R's gender determines whether R is uncle or aunt to P, not the other way around). Answer: P is R's niece.

Coded blood-relation puzzles

A third format encodes the relations using symbols and asks you to solve a chain. The legend looks like this:

The legend varies from puzzle to puzzle — always read the legend first and write it out at the top of your scratch paper. Then translate each symbol in the chain back into an English clause, and build a tree.

Method for coded chains

1. Copy the legend. Three or four symbol-meanings, written as a small table at the top of your scratch.
2. Translate left to right. 'A + B − C' becomes 'A is the father of B; B is the brother of C'. Each operator joins the two operands as one relation.
3. Build the tree. A (M) is the parent of B (M); B and C are siblings (so C is also A's child). The tree has A on top and B and C as siblings below.
4. Answer the question by reading the tree. 'How is A related to C' → A is the father of C (or just 'father').

Worked example. Using the legend above, decode A * B + C × D − E. Translate: A is the wife of B; B is the father of C; C is the mother of D; D is the brother of E. Build the tree. Generation 1: A (F) = B (M). Generation 2: their child C (F). C marries someone (unnamed) and has children D (M) and E (?, sibling of D so could be M or F — 'brother of E' tells us D is the brother, but does not fix E's gender). Generation 3: D and E. Question: how is A related to D? A is D's mother's mother — A is D's maternal grandmother. Question: how is A related to E? Same path — A is E's maternal grandmother regardless of E's gender, because grandmother applies to any grandchild.

Direction-tracking through generations

A useful mental model when walking a path on the family tree is to think of three directions:

Counting steps

The number of up-steps plus the number of down-steps in the path between two people tells you the generational gap and therefore the rough relation name:

• 0 steps: same person.
• 1 sideways step: sibling or spouse.
• 1 up step: parent. 1 down step: child.
• 2 up steps: grandparent. 2 down steps: grandchild. 1 up + 1 sideways: aunt or uncle. 1 sideways + 1 down: niece, nephew, or step-child (the latter is rare in AFCAT). 2 sideways: not a standard relation.
• 3 up steps: great-grandparent. 1 up + 1 sideways + 1 down: cousin.

Gender plus path equals relation name

For any path you can name, the answer comes from two pieces: the path shape (up, sideways, down counts) and the gender of the destination person. 'One up plus one sideways' is uncle if destination is male, aunt if destination is female. 'Two down' is grandson if male, granddaughter if female. The vocabulary table in section 4 is just the cross-product of path shapes and destination genders.

Common AFCAT trap patterns

• Trap 1 — ambiguous gender pronouns. The puzzle uses 'their' or refers to a person by a relation word that is gender-neutral ('cousin', 'spouse', 'child'). Until the puzzle fixes the gender explicitly, leave the question mark on the tree and revisit. Do not assume male just because most names sound male.
• Trap 2 — missing generation. The puzzle says 'A is the father of B, who is the son of C'. The clause 'son of C' adds C as B's parent — but C might be A (if A and C are the same person) or C might be B's mother (if C is female and A's wife). Without an explicit gender for C, you cannot collapse the two parents into one. Draw C as a separate node and join it to B; only merge C with A if the puzzle says so.
• Trap 3 — cousin versus sibling confusion. 'My uncle's son' is my cousin, not my brother. AFCAT regularly hides this with the phrasing 'my father's brother's son' — which expands to uncle's son which expands to cousin. The cousin word is gender-neutral in English; pick it whether the child is male or female.
• Trap 4 — in-law versus blood. 'My wife's brother' is my brother-in-law, not my brother. Many candidates write 'brother' because the path on the tree looks identical to a sibling line. The marriage edge breaks the blood relation; mark it on the tree and remember that anything reached through a marriage edge is an in-law.
• Trap 5 — 'only' overlooked. Without 'only', the relation 'son of my grandfather' is ambiguous (could be father or uncle). With 'only', it is forced (must be father). Always circle 'only' as you read.
• Trap 6 — speaker's gender inferred wrong. A man says, 'Pointing to a woman, she is the only daughter of my mother-in-law.' The woman is the man's wife. If you misread the speaker's gender as female, you would conclude the woman is the speaker's sister (because mother-in-law's daughter would be sister-in-law to the speaker, except the only daughter would be the speaker herself). The wording 'a man says' fixes the speaker's gender; trust it.
• Trap 7 — chain that doubles back. 'A is the brother of B; B is the daughter of C; C is the father of A.' This is self-consistent — A and B are both children of C, and A is male, B is female, C is male. The trap is not contradiction; the trap is forgetting that 'brother of B' adds A as another child of C, so the tree must show C with two children below.
• Trap 8 — option pairs that share four out of five words. When two options differ only in 'paternal' versus 'maternal' or 'uncle' versus 'aunt', that single word is the trap zone. Recompute the gender of the destination explicitly before locking the answer.

Family-tree fluency drill

The goal of practice is to make the four-step method invisible — drawing the tree should take as long as reading the prompt, not longer. Aim for sixty seconds from prompt-read to answer-locked on a clean three-generation puzzle. Build that fluency with this drill.

The 4-person, 60-second drill

Every day for two weeks, take one fresh puzzle from your practice book and time yourself. The target is to read the prompt, draw a four-person tree with gender labels and correct generation rows, and read the answer off the tree — all within sixty seconds.

What to drill if you miss the time target

• If reading the prompt takes more than ten seconds: read aloud one sentence at a time, marking each name as you encounter it.
• If labelling gender takes more than ten seconds: drill the gender-by-relation table — 'father' = M, 'mother' = F, 'son' = M, 'daughter' = F, 'brother' = M, 'sister' = F, 'husband' = M, 'wife' = F, 'uncle' = M, 'aunt' = F, 'nephew' = M, 'niece' = F.
• If drawing the tree takes more than 25 seconds: you are over-decorating. Use plain pencil, no boxes around names, just an M or F suffix and the line connectors. Speed comes from simplicity.
• If reading the answer takes more than five seconds: drill the path-to-relation table — practise naming the relation for paths like 'up-up-male' (grandfather), 'up-sideways-female' (aunt), 'down-down-male' (grandson) without looking at a chart.

Time budget per item

The Reasoning section gives you about 72 minutes for roughly 25–30 items, or about 150 seconds per item. Blood-relations is below average difficulty for prepared candidates — your target time is 60 to 75 seconds per item, banking time for non-verbal pattern items that genuinely need three minutes.

The 90-second skip threshold matters because the marginal value of a stuck blood-relations item is negative. A direction-sense item later in the section can be solved in 40 seconds; a venn-diagram item in 60. Spending three minutes on a single blood-relations item where the gender is genuinely ambiguous costs you the chance to solve two other items cleanly.

Worked AFCAT-style examples

Exam-day strategy

1. Always draw a family tree on rough paper before answering. Solving in your head doubles the error rate on three-generation items and triples it on items involving in-laws or cousins.
2. Mark gender for every named person before drawing any edge. Use M and F suffixes; if the gender is genuinely ambiguous, mark a question mark and revisit when the puzzle fixes it.
3. Identify the speaker first. Circle their name (or write SPEAKER). Every pronoun in the puzzle traces back to either the speaker or a previously-named character.
4. Circle the word 'only' whenever it appears. 'Only son' and 'only daughter' collapse a branching relation into a single forced path — they are the linchpin of pointing-statement puzzles.
5. For coded chains, copy the legend at the top of your scratch before translating the chain. Each symbol-meaning is one row; the chain becomes a sequence of English clauses you can then turn into a tree.
6. Stack generations vertically with explicit Gen 1, Gen 2, Gen 3 labels at the left margin. The most common AFCAT slip is collapsing 'grandfather' into 'father' because both sit above the speaker — the label prevents this.
7. Walk the path from the asking node to the target node in three pieces: count up-steps, sideways-steps, and down-steps. Combined with the destination's gender, this gives you the relation name in one second.
8. Distinguish blood relation from in-law by tracking which edges are marriage edges (the equal sign). Anything reached only through a marriage edge is an in-law, never a blood relation.
9. When two options differ only in 'paternal' versus 'maternal' or 'uncle' versus 'aunt', recompute the gender of the destination explicitly before locking the answer.
10. Set a 90-second skip threshold. If the path between asking point and target still has a question mark on it after a minute and a half, mark and move on — direction-sense and venn items in the same section give you better marks per minute.

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