Along time ago, the Sun and the Moon were a married couple who lived on the Earth and were great friends of the Sea.
One day, they invited the Sea to visit them but the Sea hesitated, thinking that there might not be enough room in their house. But they reassured him.
So the Sea went along with the fish and all the members of his family. Immediately the water began to rise and the Sun and the Moon, to avoid being drowned, had to climb up onto the roof and then eventually into the sky, where they are ever since.