My father and mother sitting opposite always. The father or mother, the child seat, fixed 4 way switch 4 compatible! All the way up to 4! = 24 ways. All 2 way (4!) = 48 method.
Mom and dad always sitting opposite to the father or mother sit steady, you 4 people to switch places 4! How how all the 4! = 24 how all the way be held. 2 (4!) = 48 ways.