Linda Tran

Linda Tran is Kevin Tran's mother.

Reading Is Fundamental
When her son vanishes, she goes to the police for help. A detective visits her at her house and while he's interviewing her, Kevin appears with two Angels. Mrs. Tran is relieved to see her son, but the reunion is cut short when the detective reveals himself to be Edgar, a Leviathan, who kills both Angels and kidnaps Kevin and Mrs. Tran.

There Will Be Blood
Dick Roman holds Mrs. Tran hostage and uses her life to force Kevin to translate The Word of God for him. Once Kevin is finished, Edgar instructs his men to let Mrs. Tran go, under the condition that she doesn't talk.

What's Up, Tiger Mommy?
Concerned about his mother's welfare, Kevin convinced Dean and Sam to visit his mom. After clearing through the demons secretly guarding her home, Kevin and his mom are reunited. Mrs. Tran takes the news of her son being a prophet with surprising ease, even willing to go on the job with them to ensure Kevin's safety. During the episode, she establishes herself as a devoted mother not to be taken lightly, from getting a tattoo without flinching to attacking Crowley head-on, despite knowing how dangerous he is. She, alongside Dean, Sam, and Kevin, attends the auction held by the pagan god, Plutus, for The Word Of God. After Kevin is kidnapped by Beau, Mrs. Tran offers her own soul in exchange for her son. After declining the angels' protection, Linda is possessed by Crowley, with the help of Beau, who burns her anti-possession tattoo off. In her body, Crowley kills Plutus, steals The Word of God, and escapes before Dean can kill him in Linda's body. Linda is left severely traumatized by the event, and Kevin is angry that Dean was willing to kill his mother to get to Crowley. She later disappears with Kevin, in an attempt to get away from both the Winchesters and Crowley.

A Little Slice of Kevin
When Kevin gets back to the abandoned resturant where they are hiding out, Linda, who has recovered from her possesion, dumps a bucket of holy water on him to make sure he isn't possessed. Linda reveals that in order to replicate the "demon bomb" spell Kevin used to escape Crowley so they can strike at him, she has hired a witch named Delta Mendota off of Craigslist to gather the ingredients they need which are found all over the world. When Delta arrives, Linda squirts her with holy water to make sure she is not possesed and is annoyed when Kevin shows interest in Delta. Linda is angry when it turns out Delta didn't bring them much ingredients, wanting to be paid first and is shocked that Delta betrayed them to Crowley. Crowley kidnaps Kevin and leaves a demon to kill Linda, however, she squirts him with holy water and overpowers him. Needing help to rescue Kevin, Linda calls Sam for help and brings the demon in the trunk of her car bound by a Devil's Trap so they can interogate him. Linda meets with Sam and Dean and gives them the ingredients and Kevin's notebook with instructions for the demon bomb. Interrogating the demon, they get Kevin's location, but when they get there, Sam handcuffs Linda to her steering wheel so she won't be in danger or get in the way. Sam, Dean and Castiel rescue Kevin and reunite him with Linda. Linda helps Kevin clean up a bit as Sam warns her about how calling in a witch led to this situation and tells her that they are calling in Garth to look after them and that Castiel believes he can fix Kevin's cut-off finger.

Taxi Driver
Crowley later approached her son who was alone on the boat one night. Crowley, claims to have finally captured Linda and tortured her for Kevin's location. Finally Crowley ended up getting the information from her smartphone after killing her when she refused to tell him.

Sacrifice
After Kevin is rescued, he mentions to Castiel and Dean that his mother is dead, indicating that at least he believes her to be dead.

Devil May Care
When Kevin Tran confronts Crowley in the Bunker's dungeon about the murder of his mother, Crowley places doubts into Kevin's mind as to whether he actually did kill her, saying he had been lying and pointing out that Kevin never actually saw her body. Crowley claims that Linda really is alive, but she wishes she were dead and claims that he will lead Kevin to her if he frees him. Kevin doesn't, but decides to go and look for her on his own. Dean stops him, telling him that even if Linda is still alive, she is dead in all the ways that matters.

Captives
When Kevin was killed he became a ghost and contacts Sam and Dean to look for Linda who he has learned is alive from another ghost named Candy who was held in the same place as Linda. Tracking down Candy's ghost, Sam and Dean manage to locate her and Sam goes to release her only to be trapped with her by Del, the demon who was holding and torturing Linda. Using her knowledge of electronics from helping Kevin with school projects, Linda is able to free them and they capture Del who they give Linda the pleasure of killing. Linda then demands to be taken to Kevin.

At the bunker, Linda tearfully reunites with Kevin's ghost and locates his father's ring, the object she believes him to be attached to. Despite warnings that taking a ghost with her could turn out badly, Linda decides to take and protect Kevin until Heaven is reopened, declaring that as his mother, it's her job.

Season 7

 * Reading Is Fundamental
 * There Will Be Blood

Season 8

 * What's Up, Tiger Mommy?
 * A Little Slice of Kevin
 * Taxi Driver (mentioned only)
 * Sacrifice (mentioned only)

Season 9

 * Devil May Care (mentioned only)
 * Heaven Can't Wait (mentioned only)
 * Road Trip  (photo only)
 * Captives 

Trivia

 * It is revealed in What's Up, Tiger Mommy? by Mrs. Tran that she received a tattoo on a certain part of her body in her past (most likely somewhere sexually suggestive).
 * It is mockingly revealed in What's Up, Tiger Mommy? by Crowley after possessing Mrs. Tran that she had an extramarital affair that resulted in the birth of her son Kevin Tran, though whether he was being truthful or not is unclear.
 * The actress was changed in the beginning of Season 8. The original Linda Tran was Khaira Ledeyo.
 * In Captives, Linda reveals her husband died when Kevin was a baby and Kevin never really knew him.