Blood relations involve analysis of information showing blood relationship among members of a family. In the questions, a chain of relationship is given in the form of information and on the basis of this information relation between any two members of the chain is asked. Candidates are supposed to be familiar with the knowledge of different relationship in a family.
For easy understanding of the relationships study of the following table is very useful:
| Grandfather’s son | Father or uncle |
| Grandmother’s son | Father or uncle |
| Grandfather’s only son | Father |
| Grandmother’s only son | Father |
| Mother’s or Father’s mother | Grandmother |
| Mother’s of Father’s father | Grandfather |
| Grandfather’s only daughter-in-law | Mother |
| Grandmother’s only daughter-in-law | Mother |
| Mother’s or Father’s son | Brother |
| Mother’s or Father’s daughter | Sister |
| Mother's or Father's brother | Uncle |
| Mother's or Father's sister | Aunt |
| Husband's or wife's sister | Sister-in-law |
| Husband's or wife's brother | Brother-in-law |
| Son's wife | Daughter-in-law |
| Daughter's husband | Son-in-law |
| Brother's or Sister's son | Nephew |
| Brother's or Sister's daughter | Niece |
| Uncle or Aunt's son or daughter | Cousin |
| Sister's husband | Brother-in-law |
| Brother's wife | Sister-in-law |
Some Models
* Pointing to a person, Amit said to Asha, 'His mother is the only daughter of your father.' How was the woman related to the person?
A) Aunt B) Mother C) Wife D) Daughter E) None of these
Ans: A
Hint: Daughter of your father →your's sister; the person's mother is the woman's sister. Woman is person's aunt.
* Pointing to a lady, a girl said, 'She is the daughter-in-law of the grandmother of my father's only son.' How is the lady related to the girl?
A) Sister-in-law B) Mother C) Aunt D) Mother-in-law E) None of these
Ans: B
Hint: My father's only son → My brother's Grandmother of my brother → My grandmother's Daughter-in-law of my grandmother → My mother. So, the lady is girl's mother.
* Rita told Mani, 'The girl I met yesterday at the beach was the youngest daughter of
the brother-in-law of my friend's mother.' How is the girl related to Rita's friend?
A) Cousin B) Daughter C) Niece D) Friend E) None of these
Ans: A
Hint: Daughter of brother-in-law is niece. Mother's niece → Cousin. So, the girl is the cousin of Rita's friend.
* When Amir saw Manjeet, he recalled 'He is the son of the father of the mother of my daughter.' What is Manjeet to Amir?
A) Brother-in-law B) Brother C) Cousin D) Uncle E) Nephew
Ans: A
Hint: My daughter's mother → my wife; My wife's father → my father-in-law; My father-in-law's son → my brother-in-law. So, Manjeet is Amir's brother-in-law.
* Deepak said to Nitin, 'The boy playing with football is the younger of the two brothers of the daughter of my father's wife. How is the boy playing football related to Deepak?
A) Son B) Brother C) Cousin D) Nephew E) Brother-in-law
Ans: B
Hint: Father's wife → mother; Mother's daughter → sister; Sister's younger brother → my younger brother. So, the boy is Deepak's brother.
* While walking with his friend, Mahesh meets another man whose mother is the wife of Mahesh's father's only son. How is the man related to Mahesh?
A) Son B) Nephew C) Cousin D) Uncle E) Father
Ans: A
Hint: Mahesh's father's only son → Mahesh; Mahesh's wife is mother of his son. So, the man is Mahesh's son.
* Agirl introduced a boy as the son of the daughter of the father of her uncle. The boy is the girl's?
A) Brother B) Son C) Uncle D) Son-in-law E) Nephew
Ans: A
Hint: Daughter of uncle's father → uncle's sister → mother; Mother's son → brother.
* If X is the brother of son of Y's son, how is X related to Y?
A) Son B) Brother C) Cousin D) Grandson E) Uncle
Ans: D
Hint: Son of Y's son → grandson; brother of Y's grandson → Y's grandson.
* P is the brother of D. X is the sister of P. A is the brother of F. F is the daughter of D. M is the father of X. Who is the uncle of A?
A) X B) P C) F D) M E) None of these
Ans: B
Hint: A is the brother of F, who is the daughter of D. So, A is the son of D. P is the brother of D. So, P is the uncle of A.
* K is the brother of N and X, Y is the mother of N, and Z is the father of K. Which of the following statement is not definitely true?
A) K is the son of Z B) Y is the brother of Z C) K is the son of Y
D) K is the father of X E) N is the brother of X.
Ans: E
Hint: K is the brother of N and X. So, Y who is the mother of N, and Z, who is the father of K, will be the mother and father of all the three. However, it is not mentioned whether N is a male or female. So, the statement (e) cannot be definitely true.
* E is the son of A, D is the son of B, E is married to C, C is B's daughter. How is D related to E?
A) Brother B) Uncle C) Father-in-law D) Brother-in-law E) None of these
Ans: D
Hint: C is B's daughter and D is B's son. So, D is the brother of C. E is a male married to C. So, E is the husband of C, whose brother is D. So, D is the brotherin-law of E.
* A and B are both children of C. If C is the mother of A, A is the son of C but B is not the daughter of C. How are A and B mutually related?
A) A is the brother of B B) A is the sister of B C) A is the cousin of B
D) A is the nephew of B E) None of these
Ans: A
Hint: B is the child of C but not daughter, means B is the son of C. Also, A is the son of C. So, A is the brother of B.
* C is the brother of A. B is the daughter of A. E is the sister of C, D is the brother of B. Who is the uncle of D?
A) A B) B C) C D) E E) None of these
Ans: C
Hint: D is the brother of B, who is the daughter of A. So, D is the son of A. C is the brother of A. Thus, C is the uncle of D.
* Q is the brother of R, P is the sister of Q, T is the brother of S, S is the daughter of R. Who is the cousin of Q?
A) R and P B) P and T C) Q and T D) S and T E) None of these
Ans: D
Hint: Q is the brother of R. T is the brother of S, who is the daughter of R. So, T and S are cousins of Q.
* Lakshmi and Meena are Rohan's wives. Shalini is Meena's stepdaughter. How is Lakshmi related to Shalini?
A) Sister B) Mother-in-law C) Mother D) Stepmother E) None of these
Ans: C
Hint: Shalini is meena's stepdaughter, means she is the daughter of the other wife of Rohan. So, Shalini is the daughter of Lakshmi, or Lakshmi is the mother of Shalini.
* C is A's father's nephew. D is A's cousin but not the brother of C. How is D related to C?
A) Father B) Sister C) Mother D) Aunt E) None of these
Ans: B
Hint: C is A's father's nephew, means C is the son of A's father's brother, i.e., C is the cousin of A. D is also A's cousin. So, D must be a sibling of C. But not brother of C. So, D must be the sister of C.
* A party consists of grandmother, father, mother, four sons and their wives and one son and two daughters of each of the sons. How many females are there in all?
A) 14 B) 16 C) 18 D) 24 E) None of these
Ans: A
Hint: Grandmother is one female, mother is another, wives of four sons are the four females and two daughters of all four sons are eight females. So, in all there are 1 + 1+ 4 + 8 = 14.
1. Pointing to a man, Akshay said that this man is the only son of my sister’s father-in-law. How is that man related to Akshay?
a) Son-in-law b) Brother-in-law c) Father d) Cousin
Obviously, that man is the brother-in-law of Akshay.
Ans: b
2. Pointing to a woman in the photograph, Deepti said that ‘she is the only child of my brother - in-law’s father’s sister’. How is that woman related to Deepti?
a) Cousin b) Mother c) Sister-in-law d) Daughter 
Obviously, that woman is the sister-in-law of Deepti.
Ans: c
3. Pointing to a man, a lady says that his father is the third son of her grandmother. How is the lady related to that man?
a) Cousin b) Sister c) Brother d) Either sister or cousin
Sol: 
From the diagram, it is clear that the lady is either cousin or sister of the man.
Ans: d
4. Pointing to a boy, a lady says that his mother is the only sister of her mother. How is the boy related to that lady?
a) Nephew b) Uncle c) Cousin d) Brother
Sol: From the question, lady’s mother and boy’s mother are sisters. Therefore, lady and the boy are cousins. 
Ans: c
5. Seeta said, “Mohan’s father is the only son of my father”. How is Seeta related to Mohan?
a) Grandmother b) Mother c) Sister d) Aunt
Sol: From the question, only son of Seeta’s father is Seeta’s brother, therefore, son of Seeta’s brother (Mohan) is Seeta’s nephew or Seeta is aunt of Mohan. 
6. If ‘P + Q’ means ‘P is the brother of Q,’ ‘P × Q’ means ‘P is the wife of Q’ and ‘P ÷ Q’ means ‘P is the daughter of Q’, then which of the following represents ‘A is the son of D’?
a) A ÷ C × B + D b) A + C ÷ B × D c) A × B + C ÷ D d) A ÷ B × C + D
Sol: From the question, A must be male. Going by options, choice (b) is the answer.
A + C ÷ B × D means A is the brother of C, who is daughter of B, who is wife of D. Therefore, A is son of D. 
7. If ‘P + Q’ means ‘P is the mother of Q’, ‘P ÷ Q’ means ‘P is the daughter of Q’ and ‘P – Q’ means ‘P is the sister of Q’, then which of the following represents ‘A is the husband of B’?
a) B + A – N b) B ÷ A + N c) B + N ÷ A d) B ÷ A ÷ R
Sol: From the question, A must be male and B must be female. Going by options, we get choice (c) as the answer, i.e. B + N ÷ A means B is the mother of N and N is the daughter of A, therefore, A and B are father and mother of N respectively
8. Introducing a woman, a man said, “Her mother’s husband’s sister is my aunt”. How is the man related to that woman?
a) Nephew b) Cousin c) Brother d) Either brother or cousin
From the diagram, it is clear that the man is either brother or cousin of the woman.
Ans: d
9. Pointing to Sneha, Jeevan said, “Her mother’s only daughter is my daughter”. How is Jeevan related to Sneha?
a) Brother b) Son c) Brother-in-law d) Father
Hence, Sneha is the daughter of Jeevan.
Ans: d
10. If ‘A + B’ means ‘A is the mother of B’ and ‘A × B’ means ‘A is the husband of B’, then which of the following shows ‘P is the father of Q’?
a) P × M + Q b) P + M × Q c) P + Q × M d) Q + P × M
Sol: P × M + Q
P × M ⇒ P is husband of M
M + Q ⇒ M is mother of Q.
⇒ P is father of Q. 
11. A is the sister of B, C is the father of B, D is the wife of C and E is the father of D. How is E related to B?
a) Grandmother b) Grandfather c) Father d) Son 
