[3] One day, the stepmother tells Tấm and Cám to go to the field to catch "tép" (caridina, a tropical genus of shrimp) and promises to give them a new red yếm (a Vietnamese traditional bodice) to whoever catches the most.
Realizing that her sister actually had a chance at receiving a red yếm and the day is almost done, Cám comes up with a plan to sabotage Tấm's work.
[3] When Tấm realizes that all the shrimp she has caught is gone, she cries in seeing all her hard work disappear and the impending punishment that will come from her stepmother.
Bụt (the Vietnamese equivalent to a fairy godmother, sometimes considered a tiên) appears and asks why she cries, and she tells him what happened.
Tấm would spend her time talking to the goby about her thoughts, which the fish would silently comfort her.
Suspicious about her behavior, the stepmother and the half-sister discover the fish as well as the poem by which Tấm summons it.
The stepmother plans to distance Tấm in order to kill the fish: "My daughter, the village has prohibited using the field; tomorrow you should graze our buffaloes far away, or they shall seize them.
Soon after, the sovereign hosts a festival, which he invites people from everywhere to attend, including Tấm and her family.
He calls sparrows down to help her and teaches her a poem to prevent them from eating the bran and rice: O sparrows, go down and separate these grains of rice for me Eat a grain, and I will beat you to death (Original: Rặt rặt xuống nhặt cho tao Ăn mất hạt nào thì tao đánh chết)Bụt then tells her to dig up those jars that she had buried previously.
Not forgetting her father's death day, despite the fulfilling life in the sovereign's palace, she comes back home to help her stepmother prepare for the anniversary.
The stepmother tells Tấm to climb on an areca tree to gather its fruit for the ceremony.
The sovereign immediately believes that she has been reincarnated as the bird and only spends his time with it, ignoring Cám even more.
Following her mother's counsel, Cám butchers the oriole, eats it, and then buries its feather in the royal garden.
She lies to the sovereign that she was not aware of the interaction between him and the bird, and the oriole simply flew away when she tried to feed it.
Noticing the two trees that somehow appeared in the royal garden, the sovereign believes they are also a sign from Tấm.
[4] While weaving the clothes, she hears Tấm accusing her for stealing her husband, cursing her and threatening to "hack her eyes".
The old woman says: O golden Apple, fall to my basket Your scent I'll smell, eat you I’ll not
One day, a crow flies by the stepmother's house and rests on her roof and cries out:[4] "Delicious!
")The stepmother becomes angry, but, when she finally reaches the bottom of the jar, she discovers a skull inside.
At the festival, her stepmother and Cám notice her and Tấm immediately flees in fear.
Upon returning home and changing back into her normal clothes, she discovers that one of her slippers is missing and begins to mourn for the loss of her friend.
Variations that have this change will have the sovereign set up a place to display the missing shoe for all the maidens in the country to try on, and ordered the guards to notify him of anyone who can fit it.
As Tấm was able to confirm that the shoe she took was her missing pair, the sovereign finally made himself known by entering her home.
Despite being in his presence and the stepmother and Cám beginning to scold the girl for causing enough trouble to bring guards, the sovereign speaks gently to Tấm and explains why he is at her home.
Some versions have both the stepmother and Cám arrive at the palace after her death, explaining to the sovereign that Tấm suggested the idea of her half-sister marrying him before she died.
For revenge, in some versions, Tấm tells her sister to bathe in boiling water, and Cám's vanity blinds her from reason.
Cám is either portrayed as beautiful like her sister, though lacking in qualities like grace and being hardworking, or simply plainer than Tấm.
According to Sinologist Boris L. Riftin [ru], unlike European variants of Cinderella, wherein the princess marries the prince and the tale ends, Asian variants (which include those from China and Southeast Asia) segue into the revenge of the stepfamily and the heroine's replacement by her stepsister.
[5] In the second part of the story, states Ding Naitong [zh], the heroine goes through a cycle of transformations (bird/tree/object), until she regains human form at an old woman's house.