60-second revision
- Draw a family tree: generations on separate levels, + for male, - for female, = for a married couple.
- In pointing puzzles, start decoding from the end of the sentence ('my ...') and work backwards.
- 'Only son of my paternal grandfather' is your father; 'only daughter of my mother' is your sister (or yourself, if you are female).
- Father's sister's or mother's brother's child is a cousin.
- Brother's or sister's son is a nephew; daughter is a niece.
- Only gendered words fix gender (son, brother, husband, father, uncle, nephew; daughter, sister, wife, mother, aunt, niece) — child, sibling, parent, spouse and cousin do not.
- If gender of the person asked about is never given, the answer is 'cannot be determined'.
Relation vocabulary
Most errors come from fuzzy vocabulary, not from logic. Learn the relations by generation. Paternal means on the father's side, maternal on the mother's side.
| Generation | Relations |
|---|---|
| Two above | Grandfather, grandmother (paternal or maternal) |
| One above | Father, mother, uncle, aunt, father-in-law, mother-in-law |
| Same | Brother, sister, cousin, husband, wife, brother-in-law, sister-in-law |
| One below | Son, daughter, nephew, niece, son-in-law, daughter-in-law |
| Two below | Grandson, granddaughter |
| Phrase | Means |
|---|---|
| Father's or mother's brother | Uncle (paternal or maternal) |
| Father's or mother's sister | Aunt (paternal or maternal) |
| Uncle's or aunt's child | Cousin |
| Sibling's son / daughter | Nephew / niece |
| Spouse's brother, or sister's husband | Brother-in-law |
| Spouse's sister, or brother's wife | Sister-in-law |
| Son's wife / daughter's husband | Daughter-in-law / son-in-law |
The family-tree method
Put each generation on its own level. Mark males with + and females with -, join a married couple with =, and draw a vertical line from parents to children. Siblings sit side by side on one level. Once everything is on the tree, the asked relation can be read off directly: count levels for generation and follow lines for side.
Worked example: 'D is the son of E. F is the brother of E. G is the daughter of F.' E and F are siblings on one level; D hangs under E and G under F. So G is D's cousin, and F is D's uncle.
Pointing and introduction puzzles
Statements like 'He is the son of my mother's only brother' are decoded from the end. Start with 'my', climb one link at a time, and rename each link in simple words. 'My mother's only brother' is my maternal uncle; his son is my cousin.
Coded relations
Here symbols stand for relations (for example, A * B means A is the mother of B). Translate the expression link by link from left to right into plain sentences, draw the tree, and only then answer. In 'which expression shows that...' questions, check each option the same way; usually only one keeps the generations and the genders right.
Worked example: let A ^ B mean A is the husband of B, A ! B mean A is the son of B and A ~ B mean A is the sister of B. For X ^ Y ! Z ~ W: X is Y's husband, Y is Z's son — so Y is male, which contradicts 'X is the husband of Y'. Such an option is invalid. A valid chain must respect every gender it fixes.
Family puzzles
- List each fact separately and mark the gender each one fixes.
- Use the number of generations and the number of couples as hard limits; they rule out arrangements that look possible.
- 'Daughter-in-law of K' means married to K's son; 'son-in-law of K' means married to K's daughter.
- Children of the same parents are siblings; children of siblings are cousins.
The gender trap
Only gendered words fix gender: son, brother, husband, father, uncle, nephew (male); daughter, sister, wife, mother, aunt, niece (female). Words like child, sibling, parent, spouse or cousin do not. If the question asks for a gendered relation (father or mother? nephew or niece?) and the person's gender is never fixed, the correct option is 'cannot be determined'.
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