Last Puzzles (Simple Logic Question)

A family is having a reunion on the Christmas Eve. For the toast which shall follow with the dinner, they gather around the dining table. There is a grandfather, a grandmother, two fathers, two mothers, four children, three grandchildren, one brother, two sisters, two sons, two daughters, one daughter in law and one mother in law who shall sit for the toast. Each one of them requires a separate chair. How many chairs are required?

Click For Answer