The 12th of the Sixth lunisolar month is the feast day honoring the Third Mistress of Water. She attends on the Third Mother Goddess of Water.
In Her incarnation time on Earth as a young girl, the Third Mistress once saved Emperor Lê Thái Tổ, at that time the leader of the resistance force, while he was being chased by the Míng invaders. She told him to hide his imperial robe in the cornfield, don farmer’s clothes and disguise himself as her brother. Grateful for her deed, Lê Lợi promised her that he would come back after expelling all the Míng out of the country to grant Her a title.
After bidding farewell to the gentleman, the courageous maiden kept on assisting the resistance force despite it being such an arduous undertaking. She secretly transported soldiers and munition in her little boat across the river.
When Lê Lợi succeeded in expelling the invaders and becoming the Emperor, he sent his spares to the town where he first met her, hoping he could invite her to the palace and fulfill his age-long promise. However, they found out that she had already passed away a long time ago.
Another version: According to the book “An Annex to the Genealogy of the Lê Dynasty”, Lê Lợi arranged the marriage between the maiden and his nephew, General Lê Khôi, who is sometimes believed to be one of the incarnations of the Tenth Prince. After winning the war, he returned to look for the girl but she was nowhere to be found.
One day, in his dream, a water goddess manifested and said, “I am the daughter of King Thuỷ Tề. Do you remember what you promised me? Now that you have already become the Emperor, why haven’t you delivered that promise?” He woke up and remembered the old event, realizing that the girl who helped him was a water goddess. She manifested to help him in his grand destiny. In order to commemorate her merits, he ordained the maiden as a goddess.