Riddle: Parents with two children – a son and a daughter – came to a wide river. There was no bridge there. The only way to get to the other side was to ask a fisherman if he could lend them his boat. However, the boat could carry only one adult or two children. How does the family get to the other side and return the boat to the fisherman?
First go the children.
Son comes back, and father goes on the other side to his daughter.
Then daughter goes back to pick her brother up and they both go to the other side to the father.
Son comes back to give the boat to mother who goes to the other side (to father and daughter).
Daughter jumps in and goes to her brother so they can both return to their parents.
Daughter gets off and son gives the boat back on the first side of the river to the fisherman, who goes on the other side.
There the daughter jumps in and goes to her brother to take him back to parents where she (where the whole family meets at last) returns the boat to the fisherman.