Kalam says, “Ravi’s mother is the only daughter of my mother”, How is Kalam related to Ravi? 

Maternal Uncle 

Note: ↑ 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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