De Lai, king of a northern tribe, with his daughter Au Co made a trip to visit the south. Admiring Lac Long Quan’s talent, De Lai married Au Co to Lac Long Quan. Au Co became pregnant and gave birth to a membraneous sac. The sac kept getting larger and larger, and burst on the seventh day. There were one hundred eggs in the sac, and they hatched into one hundred beautiful children.

Even though Lac Long Quan now had a family of his own, he often missed the coast and visited his mother Long Nu frequently. Au Co was unhappy with his absence.

Lac Long Quan told Au Co: "I am from the Dragon line. I like to dwell on the Coast. You are from the Fairy line, you like to be on highlands. Therefore, we can no longer live together. It is better that we separate now. You take fifty children to the highlands, and I will take fifty children down the coast..."

So, Lac Long Quan took fifty children to the coast and divided the areas to govern. He taught his people the skills of fishing and the art of tattoos so that when they dove into the water, the tattoos would scare off other marine animals.

He also educated the people about agriculture -- how to sow rice seeds and harvest rice. He showed them how rice can be cooked in a bamboo tube with some water and broiled over an open fire. When done, the bamboo tube is split and delicious cooked rice is inside.

Au Co took fifty children to the highlands, and also divided the areas to govern. The people who went to live in the jungle or the mountainous regions learned to breed animals, and worked the land to grow fruit trees for food. They lived above the ground in houses built on stilts made of bamboo trees, to avoid wild animals.

Even though Lac Long Quan and Au Co were separated, Lac Long Quan stated: "Despite the distance and separation, we must listen for one another and lend a hand to one another when needed. We must never let our bond be broken."