Blood relations is a scoring topic in the reasoning section — the questions look confusing but follow a fixed method. Once you learn to draw a quick family diagram, most questions take under a minute. Here is the approach with solved examples.
The method in four steps
- Read from the speaker’s point of view. The relation is always described relative to the person speaking or the person named.
- Use symbols. Mark male (+), female (−), and use a horizontal line for a couple, a vertical line for parent–child, and a double line for siblings.
- Fix the generations. Keep grandparents on top, parents in the middle, children below. Most errors come from mixing up generations.
- Answer only what is asked. Trace the final link carefully — many wrong answers come from stopping one step early.
Worked example 1
Pointing to a man, Reeta said, “He is the son of my grandfather’s only son.” How is the man related to Reeta?
Solution: “My grandfather’s only son” must be Reeta’s own father (the only son). So the man is the son of Reeta’s father — that makes him Reeta’s brother.
Worked example 2
Pointing to a photograph, a woman said, “She is the daughter of the only child of my mother.” How is the woman in the photo related to the speaker?
Solution: “The only child of my mother” is the speaker herself. So the girl in the photo is the speaker’s daughter.
Common relation shortcuts
- Father’s or mother’s son → brother; father’s or mother’s daughter → sister.
- Father’s brother → uncle (paternal); mother’s brother → maternal uncle.
- Son’s wife → daughter-in-law; daughter’s husband → son-in-law.
- Only son / only daughter / only child are strong clues — they usually collapse a long chain to one person.
Types of questions
Three formats dominate: pointing/photo questions (as above), coded relations (where symbols like A + B mean “A is the father of B”), and puzzle-style questions describing a whole family. For coded relations, first write down what each symbol means, then decode the expression left to right. For family puzzles, always draw the diagram — never try to hold it in your head.
Practice is what makes this topic fast. Solve five to ten questions a day, always drawing the diagram, and within a couple of weeks most blood-relation questions become near-automatic marks.
Frequently Asked Questions
What is the fastest way to solve blood relations questions?
Draw a quick family diagram using symbols for male and female and lines for couples, parent-child and siblings, fix the generations top to bottom, then trace only the relation that is asked.
What does ‘only son’ or ‘only child’ usually indicate?
These phrases are strong clues that collapse a long chain to a single person, often the speaker or the speaker’s parent, which quickly simplifies the question.
What are coded blood relation questions?
These give symbols such as ‘+’ or ‘/’ to represent relations like father or sister; you first note what each symbol means, then decode the expression step by step.