Blood Relations — UPSSSC PET Study Notes

Overview

Blood Relations is a staple reasoning topic in UPSSSC PET, typically yielding 2–3 questions in the 100-mark paper. These questions test your ability to decode family relationships from coded statements and identify how two people are related. The topic demands clarity in understanding generation levels, gender identification, and careful step-by-step relationship tracing.

Most questions come in two styles: direct relationship statements ("A is the mother of B") or pointing-style statements ("Pointing to a photograph, Ramesh said, 'Her mother is my wife'"). You must build mental or written family trees quickly, mark generations clearly, and avoid confusion between paternal/maternal sides or in-law relationships. Mastery requires understanding 15–20 core relationship terms and practicing conversion between English and Hindi terms if questions appear in Hindi.

Success in Blood Relations hinges on methodical diagram construction and not jumping to conclusions. With 20–30 practice problems, students can reach near-perfect accuracy on exam day.

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Key Concepts

• **Generation levels**: Always draw horizontal lines for the same generation (siblings, spouses, cousins) and vertical connections for parent-child or grandparent relationships. Mixing generations is the #1 source of error.

• **Gender symbols**: Use standard notation—circles or 'F' for females, squares or 'M' for males. Mark unknown genders with '?' and determine them from relationship clues like "sister," "wife," "son."

• **Direct vs. indirect relations**: Direct blood relations (parent, child, sibling) are straightforward. In-law and step-relations require extra attention—brother-in-law can mean sister's husband or spouse's brother.

• **Pointing-style questions**: When someone points at a photo and describes a relationship ("His father is my father's only son"), translate into first-person perspective: "my father's only son" = me (if male) or my brother. Build from the speaker outward.

• **Only child clues**: "Only son," "only daughter," "only brother," "only sister" are powerful constraints. They eliminate other siblings and simplify the tree drastically.

• **Spouse indicators**: Terms like "wife," "husband," "daughter-in-law," "son-in-law" tell you marriages. Draw a horizontal double-line or '=' between spouses. Children hang below the marriage line.

• **Compound relationships**: "Mother's brother" = maternal uncle; "father's sister" = paternal aunt. Break these into steps: locate the mother, then find her brother. Always traverse one link at a time.

• **Self-reference trap**: In pointing questions, watch for sentences where the speaker refers to themselves indirectly. "My father's son" might be the speaker himself or his brother—context decides.

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Formulas / Key Facts

1. **Father's/Mother's son** = self (if only child) or brother; **daughter** = self (if female, only child) or sister. 2. **Father's/Mother's father** = paternal/maternal grandfather (Dada/Nana). 3. **Father's/Mother's mother** = paternal/maternal grandmother (Dadi/Nani). 4. **Father's brother** = uncle (Chacha); **Father's sister** = aunt (Bua). 5. **Mother's brother** = maternal uncle (Mama); **Mother's sister** = maternal aunt (Mausi). 6. **Brother's/Sister's son** = nephew (Bhatija); **daughter** = niece (Bhatiji). 7. **Son's/Daughter's son** = grandson (Pota/Nati); **daughter** = granddaughter (Poti/Natin). 8. **Spouse's brother** = brother-in-law (Sala/Devar/Jija); **sister** = sister-in-law (Saali/Nanad/Bhabhi). 9. **Son's wife** = daughter-in-law (Bahu); **Daughter's husband** = son-in-law (Damaad). 10. **Father's son's wife** = If father's son = self, then my wife. If father's son = brother, then sister-in-law.

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Worked Examples

**Example 1 (Direct Statement):** A is the father of B. C is the sister of B. D is the mother of C. How is B related to D?

*Solution:*

• A is father of B → A (M) — B (?)
• C is sister of B → C (F) is sibling of B. Since C is female ("sister"), B can be male or female (brother or another sister).
• D is mother of C → D is C's mother, hence also B's mother (both are siblings sharing same parents).
• B is the **son or daughter** of D. Commonly the answer is given as **son** if the question assumes default male unless stated.

**Answer:** B is the son (or child) of D.

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**Example 2 (Only child clue):** Pointing to a woman, Neeraj said, "She is the daughter of my grandfather's only child." How is the woman related to Neeraj?

*Solution:*

• "My grandfather's only child" = Neeraj's father or mother (since grandfather has only one child).
• Assume it's Neeraj's father (common scenario).
• "She is the daughter of my father" = Neeraj's sister.
• Check: If Neeraj is male, "my father's daughter" = sister. If Neeraj is female, "my father's daughter" = self or sister. Context ("pointing to a woman" as external person) → the woman is Neeraj's sister.

**Answer:** Sister.

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**Example 3 (Complex pointing):** A man pointing to a photograph says, "The lady in the photograph is my nephew's maternal grandmother." How is the lady related to the man's sister?

*Solution:*

• Nephew = brother's or sister's son.
• Nephew's maternal grandmother = nephew's mother's mother.
• If nephew is man's brother's son: nephew's mother = man's sister-in-law (brother's wife). Maternal grandmother = brother's wife's mother = no direct relation to man's sister.
• If nephew is man's sister's son: nephew's mother = man's sister. Maternal grandmother = man's sister's mother = man's own mother.
• Lady is man's mother → she is also his sister's mother.

**Answer:** The lady is the mother of the man's sister.

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Common Mistakes

1. **Confusing "only son" with "one son"**: "My father's only son" means father has exactly one son (could be the speaker). "My father has one son" is ambiguous—could be more daughters. Always interpret "only" strictly. *Fix:* Mark "only child" as a constraint eliminating all other siblings.

2. **Mixing maternal and paternal sides**: Saying "uncle" without specifying Chacha (father's brother) vs. Mama (mother's brother) leads to wrong answers when the question is specific. *Fix:* Always note if the relation comes through father or mother and label accordingly.

3. **Gender assumption errors**: Assuming a name like "Ramesh" is male is usually safe, but names like "Suman," "Priya," "Kavita" can occasionally be trick names. Let the relationship terms (son, daughter, wife, husband) define gender. *Fix:* Mark gender only when confirmed by terms like "his," "her," "son," "daughter," or explicit mention.

4. **Ignoring the speaker in pointing questions**: Forgetting who "I" or "my" refers to causes misidentification. Students often assign "my" to the person in the photo instead of the speaker. *Fix:* Always start from the speaker's position. Label the speaker as 'S' and build relationships from there.

5. **Overcounting in-laws**: Treating brother-in-law as a single fixed relationship when it can mean three different relations: wife's brother, sister's husband, or husband's brother (context-dependent). *Fix:* Derive in-law relations from the spouse link. Draw the marriage first, then add the spouse's sibling.

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Quick Reference

• **Draw generation-wise**: Same generation = same horizontal level. Parent-child = vertical link. Mark spouse with '=' or double-line.
• **"Only" keyword = no other siblings**: Exploit this to simplify the tree instantly.
• **Maternal/Paternal distinction**: Mother's side = Nana, Nani, Mama, Mausi. Father's side = Dada, Dadi, Chacha, Bua.
• **Pointing questions = speaker's viewpoint**: Always establish "my father," "my son," etc., from speaker, not the photo subject.
• **Practice 20–30 problems**: Blood Relations rewards pattern recognition. You'll see recurring structures (grandfather's only son, nephew's grandmother, etc.).
• **Check answer choices for clues**: If options include "brother" and "cousin," and your tree shows sibling, confirm generation match before finalizing.

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**Exam Tip:** In UPSSSC PET, blood relation questions are typically 1.5–2 marks each. Spend 60–90 seconds per question. If a tree becomes complex (more than 10 people), re-read the question to see if you missed an "only" constraint that collapses branches. Speed + accuracy = smart skipping of calculation-heavy problems in favor of these logic-based sure-shot marks.