Here's a new, more complicated version of an old game where you had to help a shepherd, a wolf and a sheep cross a river on a barge that could only old two at once.
In this Japanese version, we have a family in which adults can't stand the opposite-gender kids, along with a policeman and a prisoner. So, here are the rules:
Only two people at once on the barge
The father can't stay alone with one of the daughters if the mother isn't also there
The mother can't stay alone with one of the sons if the father isn't also there
The prisoner can't stay with any member of the family without the policeman
Only the adults (the father, the mother and the policeman) can operate the barge.