Four of the following were in a certain group, which of the following that does not belong to that group?

Read the following information carefully and answer the questions given below. Eight members – M, N, O, P, Q, R, S and T of a family consists of three generations and were seated in a circular table facing centre, in which no three males were seated together. Each of them had a relationship with
M. All of them attend the seminar in a different month from April to November. No two persons attend the seminar in the same month. It is further known that either both or none of the parents are alive. Two persons were seated between P and M’s father and neither of them attends the seminar in November. The one who was seated second to the left of P attend the seminar in May. Q is married to the only sister of the one who attends the seminar in June and was seated to the immediate left of M’s daughter. Two persons were seated between N and M’s wife. Only one female attend the seminar after June. Two persons were seated between M and the one who attend the seminar in September. S and her brother attend the seminar in consecutive months. Two persons attend the seminar between P and R. T attend the seminar in August. M and his father were immediate neighbours. O, who is the son of M was seated to the immediate right of his sister and attend the seminar after M but not immediately. The one who attends the seminar in September is nephew to P and both were seated adjacent to each other. Q is from 1st generation. P is not the brother of M’s wife. Two persons were seated between Q and the one, who attended the seminar June. The one, who attended the seminar in May doesn’t face the one, who attended the seminar June. O and P are not neighbours.