Blood relations form the basis of logical reasoning problems testing your ability to identify family connections through given information.
## Core concept
Blood relations refer to connections between people based on descent (parent–child, sibling) rather than marriage. In CA Foundation exams, you'll solve problems by:
- Decoding relationship statements (e.g., "A's mother's brother" = A's maternal uncle)
- Identifying a target relationship from a chain of given relationships
- Handling ambiguous phrasing and tracking multiple family branches
The key skill is converting verbal descriptions into directional family trees.
## Common relationship symbols & shortcuts
| Person | Symbol | Common Variants | |--------|--------|---| | Father | F | Dad, papa | | Mother | M | Mom, mama | | Brother | B | Sibling (male) | | Sister | S | Sibling (female) | | Son | So | Child (male) | | Daughter | D | Child (female) | | Grandfather | GF | Paternal/maternal grandfather | | Grandmother | GM | Paternal/maternal grandmother | | Uncle | U | Father's brother, mother's brother | | Aunt | A | Father's sister, mother's sister | | Cousin | C | Child of parent's sibling | | Nephew | N | Child of sibling (male) | | Niece | Ni | Child of sibling (female) |
## Problem-solving approach
- Extract the chain: Write the relationship as a sequence. E.g., "A's mother's brother's daughter" = A → M → B → D
- Work backward from the subject: Start from A, move through each relation step by step
- Simplify: Reduce compound relations to single terms (e.g., "father's brother" = uncle; "uncle's son" = cousin)
- Verify using a small family tree: Sketch two or three generations to confirm your answer
## Worked example
Question: Pointing to a photograph, Raj says, "She is the daughter of my father's only son." Who is Raj pointing to?
Solution: - Raj's father's only son = Raj (assuming Raj is male) - Daughter of Raj = Raj's daughter - Answer: Raj is pointing to his daughter
Alternative interpretation: If "Raj's father's only son" refers to someone other than Raj, it's ambiguous—but typically it means Raj himself in such problems.
## Common exam applications
- Identifying direct relations from indirect descriptions
- Counting family members (e.g., "How many cousins does A have?")
- Directional tracing (grandparent → parent → sibling chains)
- Gender-neutral phrasing ("child," "sibling") requiring you to consider both possibilities
- Codified relationships (e.g., "A is related to B as follows...")
## Common mistakes
- Confusing maternal vs. paternal sides: Always track which parent's line you're following
- Forgetting generational gaps: "Grandmother's father" is great-grandfather, not grandfather
- Mishandling "only": "Only son/daughter" means a unique position in a generation; don't assume extra siblings exist
- Ambiguous pronouns: Re-read carefully—"he" and "she" must match the person being described
- Reversing relationships: "A's father's brother" ≠ "A's brother's father" (unless they coincide)
## Key tip for exam day
Draw a simple three-generation tree for any complex problem. This prevents mental errors and shows your reasoning if partial credit is available. For CA Foundation logical reasoning, visual clarity trumps speed.