In Mr. Robson’s family, there are one grandfather, one grandmother, two fathers, two mothers, one father-in-law, one mother-in-law, four children, three grandchildren, one brother, two sisters, two sons, two daughters and one daughter-in-law. How many members are there in Mr. Robson’s family? Give minimal possible answer option button

The family has 7 members: 1 grandfather, 1 grandmother, 1 father (the grandfather is also a father), 1 mother (the grandmother is also a mother), their son (Mr. Robson), his wife, and their child. The counts work out because family members have multiple roles - the grandfather is also a father-in-law and a grandfather, the grandmother is also a mother-in-law and a grandmother, etc.