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Blood Relations: The Family Tree Method with Generation Counting

Gender and generation symbols • Pointing-to-a-photo questions • Chains of relations • Coded relations • When gender is unknown

SSC Banking Railway 📅 Last updated: 2026-10-20

Blood relation questions are short, but they pack three or four relations into one sentence. Trying to hold them all in your head is where mistakes happen. The reliable method is to draw a small family tree on rough paper every time, even for easy questions. It takes a few seconds and removes almost all guesswork.

Use a fixed set of symbols so your trees are quick to read:

  • + next to a name for male and − for female. Leave it blank if the gender is not given.
  • A vertical line from parent down to child. Each row of the tree is one generation.
  • A horizontal single line between siblings.
  • A horizontal double line between husband and wife.

Read the question one phrase at a time, add each person to the tree, and only then answer.

Many relations are fixed by two things: the gender of the person and how many generations apart the two people are. You can count that gap directly as you read the chain of relations.

Step in the chainGeneration change
to a parent (father, mother)+1
to a grandparent+2
to a child (son, daughter)−1
to a sibling or spouse0

A total of +1 means one generation up: a parent, uncle or aunt. 0 means the same generation: sibling, cousin, spouse or in-law. −1 means a child, nephew or niece. Combine that with the gender and the line of the family, and the relation names itself.

These questions have the form "Pointing to X, Y said ...". The trick is to start from the far end of the sentence, the speaker, and work back towards the person being pointed at. Watch for "only son" or "only daughter", which often refers to the speaker or a parent.

Worked example 1: the only daughter

Pointing to a man, Riya said, "His mother is the only daughter of my mother." Riya is a daughter of her mother, and the only one, so she is the man's mother. The chain is +1 to Riya's mother, −1 to her only daughter, −1 to the man: 1 − 1 − 1 = −1, one generation below Riya. Riya is the man's mother.

Worked example 2: grandfather's only son

Pointing to a photograph, Arun said, "She is the daughter of my grandfather's only son." Arun's grandfather's only son is Arun's father. The count is +2, then −1, then −1, giving 0: the same generation. A daughter of Arun's father in his own generation is his sister.

Some questions give a list: "A is the brother of B. B is the daughter of C. C is the husband of D." Add each fact to the tree in order and mark genders as soon as a word reveals them.

Worked example 3: four people

B is the daughter of C, so C sits one row above B. C is the husband of D, so C is male and D is female, joined by a double line. A is B's brother, so A sits beside B. From A to D: 0 to his sister B, +1 to C, 0 to C's wife D, a total of +1. D is female and one generation up: A's mother.

Questions often include extra people who do not affect the answer. Draw them anyway; it is faster than deciding whether they matter.

Coded questions replace relations with symbols, for example P × Q for "P is the father of Q". Write the meaning of each symbol beside the question, then decode the expression from left to right, one pair at a time.

Worked example 4: decoding

P ÷ Q means P is the mother of Q, P − Q means P is the brother of Q, and P × Q means P is the father of Q. What does M ÷ N − O × K tell us about M and K?

M is the mother of N, N is the brother of O, and O is the father of K. Counting from K up to M: +1 to O, 0 to his brother N, +1 to their mother M, a total of 1 + 0 + 1 = 2. M is female and two generations up, so M is K's grandmother.

Worked example 5: an in-law link

How is the husband of A's father's sister related to A? Going from A to that man: +1 to the father, 0 to his sister, 0 to her husband, a total of 1 + 0 + 0 = 1. He is male and one generation up through marriage, so he is A's uncle (the father's sister's husband).

If the question never fixes a person's gender, do not guess from a name. Say the relation in a gender-free way, or choose "cannot be determined" if the options require a gendered answer.

Worked example 6: an uncle or an aunt?

X is the child of Y, and Y is the sister of Z. Z is the sibling of X's mother, so Z is X's maternal uncle or aunt. Since Z's gender is never given, the exact relation cannot be determined.

  • ✘ Assuming gender from a name, or from the word "sibling", "child" or "spouse".
  • ✘ Reading a pointing sentence from the start instead of from the speaker.
  • ✘ Forgetting that "only son" or "only daughter" can be the speaker.
  • ✘ Skipping the tree for "easy" questions.

The same step-by-step drawing habit helps with direction sense tests and with order and ranking. More reasoning methods are listed on the study hub.

Q1. Pointing to a woman, Karan said, 'She is the wife of my father's only son.' How is the woman related to Karan? easy

✅ Answer: (b) Wife

💡 Explanation: Karan is male, so his father's only son is Karan himself. The woman is the wife of Karan, so she is his wife.

Q2. Pointing to a boy, Meera said, 'He is the son of my mother's only son.' How is the boy related to Meera? easy

✅ Answer: (d) Nephew

💡 Explanation: Meera is female, so her mother's only son is her brother. The boy is her brother's son, which makes him her nephew.

Q3. A is the sister of B. C is the mother of B. D is the father of C. E is the mother of D. How is A related to D? medium

✅ Answer: (a) Granddaughter

💡 Explanation: A and B are children of C, and C is the child of D. So A is two generations below D and female: D's granddaughter. E is extra information.

Q4. P × Q means P is the father of Q, P + Q means P is the sister of Q, and P − Q means P is the brother of Q. If A × B + C − D, how is A related to D? medium

✅ Answer: (c) Father

💡 Explanation: A is the father of B. B is the sister of C, and C is the brother of D, so B, C and D are siblings. A is therefore the father of D.

Q5. R is the brother of S. S is the sister of T. How is T related to R? medium

✅ Answer: (c) Cannot be determined

💡 Explanation: R, S and T are siblings, but the question never gives T's gender. T could be R's brother or sister, so the relation cannot be determined.

Q6. Introducing a man, a woman said, 'His wife is the only daughter of my father.' How is the man related to the woman? easy

✅ Answer: (d) Husband

💡 Explanation: The only daughter of the woman's father is the woman herself. The man's wife is therefore the woman, so he is her husband.

Can I assume a person's gender from their name?

No. Use only the gender the question states or implies through words such as son, wife or brother. If gender is never fixed, the correct answer may be 'cannot be determined', and examiners often include it as an option for that reason.

How do I handle in-law relations?

Draw the marriage as a horizontal double line between spouses. A spouse's parent is a parent-in-law, a spouse's sibling or a sibling's spouse is a brother-in-law or sister-in-law, and both stay in the same generation as the person.

All problems and solutions on this page are original. No outside facts are relied on; every numeric answer is recomputed by software before publishing.

How this page was prepared. Drafted with AI assistance (Claude (Anthropic AI model)) from the sources listed above. 5 calculations on this page were recomputed by software and matched. Automated checks also covered structure, internal links and duplicate text. Software checks cannot confirm facts. Reviewed by praveenkumar on 2026-10-20 against the sources listed above.

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