Pointing to a woman a man said, “She is the only sister of my mother’s father – in – law’s only son”. How is woman related to man?

Aunt

↑ or ↓ ⇒ Upward or downward line shown "generation gap" .

   =    ⇒ Double lines shown "relation b/w Husband & Wife"

   —   ⇒ single line shown "relation between them other than Husband & Wife".

   +   ⇒ Plus sign shown " Male".

   -   ⇒ minus sign shown " Female".

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