Blood Relations: Solve Any Question With a Family Tree

Blood relation questions test whether you can follow a chain of relationships without getting lost. The secret is to stop holding the chain in your head and draw it instead.

The family-tree notation

Use the same symbols every time:

• Square or + for a male, circle or − for a female, ? when gender is not given
• Horizontal line between siblings
• Vertical line from parent to child
• Double line (=) between husband and wife

Generations go top to bottom: grandparents, then parents, then children.

Relation words you must know

Relation	Means
Paternal	on the father’s side
Maternal	on the mother’s side
Uncle (paternal)	father’s brother (chacha/tau)
Uncle (maternal)	mother’s brother (mama)
Aunt	father’s sister (bua) or mother’s sister (mausi)
Brother-in-law	spouse’s brother, or sister’s husband
Nephew / niece	your sibling’s son / daughter
Cousin	your uncle’s or aunt’s child

Method: start from the end of the sentence

Many questions read like “A is the son of B’s father’s only son”. Start from the last person mentioned and work backwards:

1. B’s father.
2. B’s father’s only son: if B is male, that is B himself; if B is female, it is her brother.
3. That person’s son is A.

Notice how the answer changed with B’s gender. That is the most important idea in this chapter.

The gender trap

Examiners rely on gender to make questions tricky. “My mother’s only son” is me if I am male, and my brother if I am female.

• If the question gives gender, mark it on your tree at once.
• If gender is not given and the answer depends on it, the correct option is usually “cannot be determined” or “brother or sister”.
• Never assume gender from a name. Use only what the question states.

Coded relations

Some questions define symbols, for example:

• “P + Q” means P is the father of Q
• “P × Q” means P is the sister of Q

Then ask what “A + B × C” means. Translate one symbol at a time: A is B’s father, and B is C’s sister, so B and C are siblings and A is C’s father.

Worked example

Pointing to a photograph of a girl, a man said, “Her father is my mother’s only son.”

• The man’s mother’s only son is the man himself (he is male).
• So the girl’s father is the man.
• She is his daughter.

Practice tips

1. Draw the tree even for easy questions; the habit makes hard questions easy.
2. Mark gender only when the question states it.
3. Read every option: “brother or sister” is often the correct answer to an incomplete question.

Practise with our blood relation MCQs. Each explanation walks through the family tree step by step.