Who sits to the immediate right of Q ?

K sits third to the left of N :-

Now only one person sits between Q and N. So Q is either sitting second to the right of N or second to the left of N.
If Q were to sit second to the right of N :-
N’s sister sits to the immediate right of Q. Only two persons sit between N’s sister and N’s mother. J sits to the immediate right of N’s mother. P sits to the immediate right of M. N’s brother sits third to the right of P. N’s wife sits second to the left of N’s brother. Only three persons sit between N’s wife and L.
This leads us to :-


Now no matter who the father of N is, there is no possible arrangement where N's son sits second to the right of N's father and there are only 2 people sitting between N's daughter and N's Father.
Hence this case isn't possible and Q has to sit second to the left of N.

Now N's sister has to sit between N and Q.
Since there are only 2 seats between N's sister and mother, N's mother can be seated second to the right of N or diametrically opposite of N.
If N's mother was seated diametrically opposite to N, she would be to the immediate left of K and hence J won't be able to sit immediately right of N's mother.


Now since J sits to the immediate right of N's mother and M and P are seated adjacent to each other with P sitting on the right of M, P has to be N's mother.


L can be seated next to N or diametrically opposite N. Since 3 people are sitting between L and N's wife, L can't be diametrically opposite N.

Now only O can be N's father, neither Q nor M can stay true to the conditions of N's son sitting second to the right of them and N's daughter sitting 2 places away.
Hence the final arrangement becomes :-



N's sister sits to the immediate right of Q.