'A @ B' means 'A is the husband of B'.

'A & B' means 'A is the mother of B'.

'A # B' means 'B is the daughter of A'.

If G # H & I @ J & K, then how is H related to J?

Mother-in-law

ATQ, 

               H is mother in law of J

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Please note:

  l   ⇒ Vertical line shown "generation gap".

 =  ⇒ Double lines shown "relation of spouse" 

—  ⇒ Horizontal line shown "relation in same generation other than spouse".

     ⇒ Rectangular box shown " Male".

     ⇒ Circular box shown " Female".

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