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Quantitative Aptitude · Blood Relations

Generation-Based and Mixed Relations in Blood Relations (CA Foundation)

Updated 1 October 2026

Generation-based blood relation questions link several people through chains such as father's sister's son. You solve them by drawing a family tree, fixing each person's generation and gender, and reading the chain one link at a time. Then you match the final link to the relation named in the options.

Understand Generation-Based and Mixed Relations

A blood relation question gives you a chain of statements and asks how two people are related. In mixed questions the chain crosses two or three generations and includes in-laws, cousins, uncles, aunts, nephews and nieces.

Start with generations. Grandparents are the top level. Parents, uncles and aunts sit one level below. You, your siblings and your cousins are on one level. Your children, nephews and nieces are one level lower. Moving up or down a level is the main thing to track.

Next, learn the key terms. Paternal means father's side. Maternal means mother's side. A paternal uncle is your father's brother. A maternal uncle is your mother's brother. A cousin is the child of your uncle or aunt. A nephew is a brother's or sister's son. A niece is a brother's or sister's daughter.

In-laws come through marriage. Your spouse's parents are your parents-in-law. Your brothers-in-law are your spouse's brother, your sister's husband and your spouse's sister's husband. Your sisters-in-law are your spouse's sister, your brother's wife and your spouse's brother's wife. Your son's wife is your daughter-in-law.

The skill is not memory alone. It is bookkeeping. Write down each person's generation and gender as the chain unfolds. When the information is not enough to fix a gender, the correct answer may be 'cannot be determined'.

Key formulas to remember

Paternal uncle
Father's brother
Father's elder or younger brother. Father's sister is the paternal aunt (bua).
Maternal uncle
Mother's brother
Mother's sister is the maternal aunt (mausi). Mother's brother's wife is also an aunt.
Cousin
Child of one's uncle or aunt
Gender is not fixed by the word 'cousin'. Use 'cousin brother' or 'cousin sister' only when stated.
Nephew and niece
Nephew = brother's or sister's son; Niece = brother's or sister's daughter
They are one generation below you.
Brother-in-law
Spouse's brother, sister's husband or spouse's sister's husband
Always male.
Sister-in-law
Spouse's sister, brother's wife or spouse's brother's wife
Always female.
Generation count
Grandparent +2, Parent +1, Self 0, Child -1, Grandchild -2
Siblings, cousins and spouses are at level 0.
Father's or mother's only son/daughter
Father's only son = self or brother; mother's only daughter = self or sister
'Only' removes other siblings of the same gender.

How to solve Generation-Based and Mixed Relations questions

Use this method for any multi-step blood relation question. It works whether the data is a story or a chain.

  1. 1Read the question once and note who you must find the relation between. Underline the starting person.
  2. 2Write each statement as a small link: person, gender if known, and generation level (use +1 for older, -1 for younger).
  3. 3Start from the person who is 'I' or 'she' or 'he' in the question. Move one link at a time, never skipping.
  4. 4Draw a quick family tree with squares for males, circles for females, a line for marriage and a vertical line for children.
  5. 5Change an unknown gender only when a word fixes it, such as son, sister or uncle. Otherwise leave it open.
  6. 6Compare the two target people: find their generation gap and whether they are on the same side (paternal or maternal).
  7. 7Name the relation using the gap and the side. Same level and children of siblings means cousin; one level lower and child of a sibling means nephew or niece.
  8. 8Check every option against the tree. If the gender is unfixed, look for 'cannot be determined'.

Quickest way: Link-by-link shorthand under time pressure

When to use it: Use this for chain questions such as 'A is the father of B's mother' where you have about 40 seconds.

  1. Write short symbols: F for father, M for mother, B for brother, S for sister, So for son, D for daughter, H for husband, W for wife.
  2. Turn the chain into a string and read it from the starting person, for example: 'my mother's brother's son' becomes M-B-So.
  3. Cancel pairs that return to the same person. A parent's child could be yourself or a sibling, so cancel carefully and keep that possibility in mind.
  4. Count generation steps: each parent step is +1, each child step is -1. A net 0 with a sibling step between suggests cousin.
  5. Match the result to an option. If two options remain, test the one that depends on gender with a quick sketch.
  6. Skip a question if you cannot fix the chain in about a minute. A wrong answer costs 0.25 marks, so guess only when you can eliminate at least one option, and avoid wild guesses.

Common mistakes in Generation-Based and Mixed Relations

  • Mixing up paternal and maternal uncles

    Both are called 'uncle' and students read the side too fast.

    Fix: Paternal means father's side, so father's brother. Maternal means mother's side, so mother's brother. Write F or M beside the first link.

  • Assuming 'cousin' means a male

    Everyday language treats the word as neutral, and students wrongly assume a gender when choosing among options.

    Fix: If the gender is not stated, do not assume it. Choose 'cannot be determined' when options ask for brother or sister.

  • Treating 'my father's son' as always my brother

    Students forget that the speaker may himself be the son.

    Fix: Father's son is brother or self. Look for 'only' or for gender and name clues before concluding.

  • Dropping a generation in a long chain

    Several links are processed in the head without marking levels.

    Fix: Write +1, 0 or -1 next to every link and add them at the end.

  • Confusing nephew with cousin

    Both are sibling-related and both appear in the options.

    Fix: A nephew or niece is one level below you and is a sibling's child. A cousin is at your level and is an uncle's or aunt's child.

  • Ignoring in-law rules

    Students treat a spouse's siblings as blood relatives and mismatch the term.

    Fix: Spouse's brother, sister's husband and spouse's sister's husband are brothers-in-law. Spouse's sister, brother's wife and spouse's brother's wife are sisters-in-law. Use the marriage line in the tree.

Worked examples

Example 1

Pointing to a man, Rita says, 'He is the son of my mother's only brother.' How is the man related to Rita? (A) Nephew (B) Cousin (C) Brother (D) Uncle

Show the solution
  1. Start with Rita and go to her mother's brother. Rita's mother is one level above Rita.
  2. Her mother's brother is Rita's maternal uncle and he is also one level above Rita.
  3. The man is the son of that uncle, so he is one level below the uncle and therefore at Rita's level.
  4. The man is male and is the son of Rita's maternal uncle, so he is her cousin.
  5. Among the options, only cousin matches. Brother would mean he shares Rita's parents, which is not stated.

Answer: (B) Cousin

Example 2

A is the brother of B. B is the daughter of C. C is the wife of D. How is D related to A? (A) Father (B) Husband (C) Uncle (D) Son

Show the solution
  1. A is the brother of B, so A and B are siblings. A is male.
  2. B is the daughter of C, so C is the parent of both A and B. C is the mother.
  3. C is the wife of D, so D is the husband of the mother.
  4. The couple's children are A and B, so D is the father of A.
  5. Check the options. Husband and son cannot apply to A, and uncle would not fit because D is the direct parent.

Answer: (A) Father

Example 3

Pointing to a photograph, Manoj says, 'She is the daughter of the only son of my father's father.' How is the girl related to Manoj? (A) Cousin (B) Sister (C) Niece (D) Aunt

Show the solution
  1. Manoj's father's father is Manoj's paternal grandfather, two levels above Manoj.
  2. Manoj's father is a son of this grandfather. The grandfather has only one son, so that only son is Manoj's father.
  3. The girl is the daughter of Manoj's father.
  4. Manoj is a son of the same father, and the girl is a daughter of that father, so she is Manoj's sister.

Answer: (B) Sister

Exam tips

  • Draw a mini tree for every question that has three or more links. The 20 seconds spent drawing usually saves a wrong answer.
  • Watch the key words 'only', 'paternal', 'maternal' and 'wife of'. They decide who the person can be.
  • If a statement leaves a gender open, check whether 'cannot be determined' is an option before picking a gendered answer.
  • In this paper a wrong answer costs 0.25 marks. Guess when you can eliminate at least one option, avoid wild guesses, and skip and return if time remains.
  • Practise reading chains from the end back to the start. Some questions are easier when you reverse the direction.

Practice questions from Blood Relations

Generation-Based and Mixed Relations: frequently asked questions

What is the difference between a maternal uncle and a paternal uncle?

A paternal uncle is your father's brother. A maternal uncle is your mother's brother. Both are one generation above you, but they are on different sides of the family tree.

Is a cousin always male in blood relation questions?

No. A cousin is the child of your uncle or aunt, and can be male or female. Unless the question states the gender, you cannot assume it.

How do I solve multi-step blood relation problems quickly?

Turn each statement into a short symbol such as F, M, B, S, and track the generation level of each link. Sketch a small tree and read the chain step by step. Then match the result to the options.

What is the difference between a nephew and a cousin?

A nephew is the son of your brother or sister, so he is one generation below you. A cousin is the child of your uncle or aunt, so he or she is at your own generation.