Blood Relation Reasoning for RBI Assistant 2026: Concepts, Tricks & Practice Questions

Blood Relations is an important topic for competitive exams like RBI Assistant, often carrying 2-3 marks in Prelims and 5-8 marks in Mains. Candidates are usually asked to determine relationships, identify family members, or interpret coded family trees based on the information provided.

Learning the basic concepts, common patterns, and shortcut tricks can help candidates solve blood relation questions in less time during the exam. Regular practice with different types of questions also improves accuracy and logical thinking.

Read more to get Prelims-level understanding, and know how to represent and establish relationships. Mastering these concepts is key to securing marks in the reasoning section.

Blood Relations Overview

Blood Relations questions require identifying family relationships and representing them using a family tree. The basic structure includes immediate family members such as parents, children, siblings, and grandparents, while relatives can belong to the paternal (father’s side) or maternal (mother’s side). Marriage introduces in-law relations like father-in-law and sister-in-law, which may have multiple meanings. 

To solve such questions, candidates often draw a family tree where older generations are placed above younger ones. Gender must be clearly stated or inferred, as some terms like spouse, cousin, child, parent, and sibling are gender-neutral. Standard notations include boxes for males, circles for females, and lines to show relationships.

Topic-Wise Blood Relations Problems

Practising topic-wise Blood Relation problems helps candidates understand different question patterns that frequently appear in the reasoning section. Instead of solving random questions, studying them category-wise allows aspirants to build a strong conceptual foundation and improve speed and accuracy.

Blood Relations Problem 1 (8 Members, 3 Married Couples)

Problem Setup: An 8-member family with three married couples.

Given Relations:

1. R is the brother-in-law of G.

2. C has two children, H and G.

3. G is married to F.

4. F is the father of I.

5. D is the mother of H.

6. Males are more than females.

7. E is the brother-in-law of D.

Solution:

From (3) and (4), G (female) is married to F (male), who is I's father. From (2) and (5), C and D are a married couple, parents of H and G. To satisfy "three married couples" and R being G's brother-in-law, H (female) must be married to R. From (7), E (male) is C's brother. Applying "males are more than females," I is male.

The pair G and I consists of a female and a male.

Blood Relations Problem 2 (8 Persons)

Problem Setup: An 8-person family.

Given Relations:

1. F is the son of E.

2. A is a male.

3. D is married to B, who is the daughter of A.

4. E is the brother of D.

5. H is the mother of F.

6. E is the father of G.

7. H has only one son and one daughter.

8. C is the daughter of D.

Solution:

From (3), D (male) is married to B (female), daughter of A (male). From (4), E (male) is D's brother. From (1) and (5), E and H are a married couple, parents of F (male). From (6) and (7), G (female) is E's daughter, sister of F. From (8), C (female) is daughter of D and B.

D is the brother of H's husband (E), making D the brother-in-law of H.

Blood Relations Problem 3 (7 Members, 3 Males)

Problem Setup: A 7-member family with three male members (four female members).

Given Relations:

1. Aruna is the mother of Paras.

2. Paras is the brother of Gauri.

3. Karan is married to Gauri.

4. Sonia is the sister of Karan.

5. Karan is the son of Liza.

6. Liza is the grandmother of Manish.

Solution:

Aruna (female) is mother of Paras (male) and Gauri (female). Karan (male) is married to Gauri. Karan is son of Liza (female). Sonia (female) is Karan's sister. Liza is grandmother of Manish. Given three males, Manish must be male.

Gauri is married to Karan, Liza's son. Therefore, Gauri is Liza's Daughter-in-law.

Blood Relations Problem 4 (9 Persons, 3 Generations, No Single Parent)

Problem Setup: A 9-person family with three generations. No single person is a parent.

Given Relations:

1. U and H are the children of S.

2. S has only one daughter.

3. S is the son-in-law of B.

4. H is a male member.

5. Q, who is the only son of B, is married to X.

6. A is the father of K.

7. E, who is the only sister of K, is not married.

Solution:

From (1), (2), (4), H is male, U is female, both children of S (male). From (3), S is married to B's daughter. From (5), Q is B's only son, married to X (female). This implies S's wife is Q's sister. From (6) and (7), A is father of K, and E is K's only unmarried sister.

X is married to Q, who is the brother of S's wife. K is the child of A and S's wife's brother. Therefore, X is the Sister-in-law of K.

Blood Relations Problem 5 (7 Members, 3 Married Couples, Gender Count, No Single Parents)

Problem Setup: Seven members, three married couples, three generations. Number of females is one more than males (4 females, 3 males). No single parents.

Conditions and Placement:

1. T is married to V.

2. R is married to the only daughter of V.

3. P has no siblings.

4. P is the granddaughter of S.

5. S is the father of K.

6. V and K have the same gender.

7. U has only one son.

8. K has a brother.

9. K is an unmarried girl.

Solution:

K is an unmarried girl. From (5), S is K's father. From (8), K has a brother. So S is father of K and her brother. From (9), U is S's wife (mother of K and her brother), U has only one son (K's brother). P is S's granddaughter (from his son). V and K are same gender, so V is female. T is married to V, so T is male. R is married to V's only daughter. Given the gender count, the full family tree can be deduced.

S is the father of T.

Blood Relations Problem 6 (8 Members, 3 Generations, More Females than Males, All Males Married)

Problem Setup: Eight persons, three generations. Either none or both parents are alive. More females than males. Three couples, and all males are married.

Conditions and Placement:

1. S and K are not married but they are cousins.

2. P has two children: a son and a daughter.

3. R is the son-in-law of H and H is the mother-in-law of J.

4. I is the mother of S.

5. H is married to D, who is a parent of W.

6. W is a niece of R.

7. H is the sister-in-law of A, who is the mother of both K and T.

8. Neither W nor X has any sibling.

9. K is the only grandson of X.

Solution:

From (3), R is the son-in-law of H (female), and J is married to H's son. So H and D are a couple, and D is male. From (5), D is parent of W. From (6), W is niece of R. From (7), H is sister-in-law of A. A (female) is mother of K and T. From (9), K is only grandson of X (male).

P is the father of Q.

Blood Relations Problem 7 (8 Members, 3 Generations, No Single Parent, "Only" Constraints)

Problem Setup: Eight members in a family across three generations. No single parent.

Conditions and Placement:

1. F is the only daughter of V, who is the daughter-in-law of G.

2. G is married to M.

3. G is of the same gender as W.

4. W and Z are siblings of F.

5. D is the son-in-law of C.

Solution:

From (1) and (2), V is female, daughter-in-law of G, so G has a son married to V. From (3), G is married to M. From (4), W and Z are siblings of F. Since F is the only daughter of V, W and Z must be sons of V. From (3), G is of the same gender as W (male). So G is male, M is female. V's husband is G's son (let's call him C). So C is male. From (5), D is son-in-law of C, meaning D is married to C's daughter (F). So D is male.

The male members are G, C, W, Z, D. Thus, there are five male members.

Blood Relations Problem 8 (Nine Members, "Only" and "Neither/Nor" Constraints)

Problem Setup: Nine members in a family.

Conditions and Placement:

1. F is the mother of R, who is the only son of X.

2. H is the sister-in-law of A, who is the mother of both K and T.

3. H is married to D, who is a parent of W.

4. W is a niece of R.

5. Neither W nor X has any sibling.

6. K is the only grandson of X.

Solution:

From (1), F (female) is R's mother. R is the only son of X. So F and X are a married couple, and R is their only son. From (6), K is the only grandson of X. Since R is X's only son, K must be R's son. From (2), A (female) is mother of K and T. So A is R's wife. From (4) and (5), W is R's niece, and neither W nor X has siblings.

F is the mother-in-law of D.