Blood Relations — Study Notes

Overview

Blood Relations questions test your ability to decode family relationships and trace connections between individuals. In SSC MTS, you'll typically encounter 3–5 questions based on this topic. The problems come in two main styles: **family-tree puzzles** where you build a diagram from clues, and **pointing-style questions** where one person describes another's relationship ("Pointing to a photo, Ram said…").

Mastering Blood Relations requires two skills: knowing the standard relationship vocabulary (paternal uncle, sister-in-law, maternal grandfather) and systematically converting word clues into a visual tree or chart. Many students lose marks by rushing or misinterpreting "brother-in-law" or "daughter-in-law." The key is to work methodically — mark gender, generation, and marriage links clearly. With practice, these questions become some of the easiest scoring opportunities in the Reasoning section.

Most SSC MTS Blood Relations questions are straightforward if you avoid common traps like confusing maternal and paternal sides or miscounting generations. Spend 1–2 minutes per question and always draw a quick diagram.

Key Concepts

• **Generation levels**: Arrange family members in horizontal layers — grandparents at top, parents in middle, children (your generation) below, and grandchildren at bottom. This prevents mixing up aunts with cousins.

• **Gender marking**: Use standard symbols — **male = square or +**, **female = circle or –**. Always mark gender explicitly; many wrong answers result from assuming gender incorrectly.

• **Marriage link**: Represent spouses with a horizontal line or '=' sign connecting them. Children branch downward from the marriage line. A person can have only one spouse in standard problems unless remarriage is mentioned.

• **Sibling identification**: Siblings share the same parents and sit on the same generation level. Brother and sister are direct; brother-in-law and sister-in-law involve a marriage connection (your spouse's sibling or your sibling's spouse).

• **Maternal vs. Paternal**: Maternal relatives are from the mother's side; paternal from the father's side. Maternal uncle = mother's brother. Paternal uncle = father's brother. Mixing these is a common error.

• **"Only" keyword**: "Only son" or "only daughter" means no other children of that gender. "Only child" means no siblings at all. This constrains the tree significantly.

• **Reverse relationships**: If A is B's father, then B is A's son or daughter. If A is B's sister, then B is A's brother or sister. Practice flipping relationships both ways to verify your diagram.

• **Counting paths**: To find an unknown relationship, trace the path from person X to person Y through the family tree. Each hop up or down or sideways tells you part of the relationship (e.g., up to parent, across to sibling, down to child).

Formulas / Key Facts

1. **Father's/Mother's brother** = Uncle (paternal uncle if father's brother, maternal uncle if mother's brother). 2. **Father's/Mother's sister** = Aunt (paternal or maternal aunt accordingly). 3. **Brother's/Sister's son** = Nephew. **Brother's/Sister's daughter** = Niece. 4. **Son's/Daughter's child** = Grandchild (grandson or granddaughter). 5. **Father's father** = Paternal grandfather. **Mother's father** = Maternal grandfather. 6. **Spouse's brother** = Brother-in-law. **Spouse's sister** = Sister-in-law. 7. **Sibling's spouse** = Also brother-in-law or sister-in-law (same term, different paths). 8. **Son's wife** = Daughter-in-law. **Daughter's husband** = Son-in-law. 9. **Husband's/Wife's parent** = Father-in-law or Mother-in-law. 10. **Cousin** = Uncle's or Aunt's child (first cousin).

**Common shorthand**: Use initials in diagrams (F=father, M=mother, B=brother, S=sister, H=husband, W=wife, D=daughter, So=son) to save time.

Worked Examples

**Example 1**: Pointing to a man, Seema said, "He is the son of my father's only son." How is the man related to Seema?

**Solution**:

• Seema's father's only son = Seema's brother (assuming Seema has no other brothers) **OR** Seema herself if she is female and the only child. But "only son" means male, so Seema's father has exactly one son.
• If Seema has a brother, that brother is "my father's only son."
• The man is the **son of Seema's brother** → the man is Seema's **nephew**.

**Alternate interpretation**: If Seema's father has only one son and Seema is female, the only son could be Seema's brother. But if Seema were the only child and male, "only son" = Seema herself. Then "son of my father's only son" = son of Seema = Seema's son. Context usually clarifies gender. In most SSC problems, "only son" + speaker is female → speaker has one brother, man is nephew.

**Answer**: Nephew.

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**Example 2**: A is B's sister. C is B's mother. D is C's father. E is D's mother. How is A related to D?

**Solution**: Draw the tree:

• D (gender unknown, assume male for notation)
• D's child = C (B's mother, so C is female)
• C's children = A and B (A is B's sister, so A is female, B could be male or female)

Generations:

• E (top) → D (one down) → C (one down) → A and B (one down).

A is C's daughter. C is D's daughter. So A is D's **granddaughter**.

**Answer**: Granddaughter.

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**Example 3**: Introduce a man, Anjali says, "His brother's father is the only son of my grandfather." How is Anjali related to the man?

**Solution**:

• "Only son of my grandfather" = Anjali's father (since Anjali's grandfather has only one son).
• "His brother's father" = the man's father.
• So the man's father = Anjali's father.
• Therefore the man is Anjali's brother.

But the question asks Anjali's relation to the man → Anjali is the man's **sister**.

**Answer**: Sister.

Common Mistakes

1. **Confusing brother-in-law types**: Students forget brother-in-law can mean spouse's brother OR sister's husband. Always check which path applies. **Fix**: Draw the marriage link clearly and trace both possibilities if unsure.

2. **Assuming gender without clues**: If the problem says "child" or "sibling" without specifying male/female, don't assume. Re-read for gender hints like "his," "her," or role names (uncle = male, aunt = female). **Fix**: Mark gender as "unknown" and see if the question's answer choices force a conclusion.

3. **Misreading "only"**: "Only son" ≠ "only child." Only son means no other sons, but daughters may exist. **Fix**: Write down exactly what "only" restricts (sons, daughters, or children) before building the tree.

4. **Mixing maternal and paternal**: Calling mother's brother a paternal uncle is wrong. **Fix**: Trace back to mother's side vs. father's side explicitly. Use M-uncle and P-uncle shorthand if needed.

5. **Overcounting generations**: Moving from grandfather to father to son is two generation steps down, not three. Counting the starting person as a step causes off-by-one errors. **Fix**: Count the **links** (arrows), not the **nodes** (people).

Quick Reference

• Always draw a family tree or chart — visual diagrams prevent logical errors.
• Mark male/female and generation clearly; use symbols (□ = male, ○ = female).
• "Only son/daughter/child" strictly limits siblings — read carefully.
• Spouse's sibling = sibling-in-law; sibling's spouse = also sibling-in-law.
• Maternal = mother's side; Paternal = father's side — don't mix.
• Practice reverse relationships: if X is Y's uncle, then Y is X's nephew/niece.