Since Then: Kate occasionally helped with Aaron on the island, but she doubted she'd ever make a good mother herself. When she escaped the island though, she found herself carrying Aaron while Claire was left behind. She chose to raise the baby herself, claiming she'd given birth on the island. The guilt of raising someone else's child eventually convinced her to return to the island to find Claire again. In her afterlife, witnessing again Aaron's again woke Kate up.
Origin: Ben ordered Kate kidnapped to manipulate Jack
Since Then: Ben shared breakfast with Kate, mocking her affections for Sawyer. He monitored her in the cages over the next few day, and watched her and Sawyer have sex. They next met as the survivors trekked to the radio tower. Both lived in the Barracks with Locke for some time, and Kate broke Miles into Ben's room. Ben later had to honor an agreement Kate had made with Richard and let the survivors fly to the freighter.
Off the island, Ben hired a lawyer to intimidate Kate, scaring her about losing Aaron and ultimately convincing her to return to the island. On the island, in 1977, Kate took young Ben to the Others to save his life. The two spent a short time together in 2007, and Kate helped free Ben from under a fallen tree.
Origin: Charlie accompanied Kate to the cockpit, hoping to retrieve his heroin. She told him she was happy he came.
Since Then: The two shortly after went on another mission to find a radio signal. Later, after Charlie was kidnapped, Kate searched for him with Jack and witnessed his resuscitation.
The two interacted rarely after this, but Charlie's work in the Looking Glass let Kate find rescue and spend years in Los Angeles, raising Aaron, Charlie's surrogate son, as her own. After death, Kate thanked him for his sacrifice and helped him remember his life.
Origin: The two sorted through clothes one day on the beach
Since Then: When Claire went into labour, Kate delivered her baby. Kate spent time with Claire in the barracks. She raised Aaron for her off-island, then returned to the Island to help reunite him with his mother. She even tried resetting time to give Claire a chance to raise Aaron from the start. When the two reunited Claire initially tired to kill Kate, but the two quickly reconciled. Kate convinced Claire to return to civilization, Kate offered to continue to help raise Aaron. In the flash sideways, Kate and Claire continued to help each other. They awoke together over Aaron's birth.
Since Then: While still on the run for murdering her stepfather, Kate married Kevin Callis, a cop with the Miami Police Department. Kevin was not aware of Kate's fugitive status nor did he even know Kate's real name; she had revealed her name to him as 'Monica'. Sometime around six months into the marriage, Kate called the Marshal and pleaded with him to stop pursuing her, citing her love for Kevin. The Marshal made her a tantalizing, yet questionable deal, saying he will leave her alone if she really stays put; it's a rhetorical offer because he knows Kate has an inability to stay put in one place for very long. Driven by the Marshal's pursuit of her as well as a pregnancy scare, Kate decides to leave Kevin. She drugs him and reveals her fugitive status to him before leaving him tearfully behind.
Origin: Edward Mars was the U.S. Marshal assigned to bring Kate in for the murder of her biological father.
Prize: Kate's freedom. Kate wants to run, Mars wants her apprehended.
Fuel: Edward Mars caught Kate at a bus station, but she escaped after a car accident involving a horse ("What Kate Did"). Mars then found the toy airplane that had belonged to Kate's childhood sweetheart and put it in a safe deposit box ("Born to Run"), hoping Kate would come looking for it ("Whatever the Case May Be"). Rather than come to him, she robbed the bank. She would also call Mars at his office, asking for him to stop chasing her. He taunted her that he would, only if Kate could stop running, which she could not ("I Do"). Mars recaptured Kate in Australia, and was flying her back to the U.S. to face prosecution when the plane crashed ("Pilot, Part 2"). Edward Mars was fatally wounded in the crash, but revived long enough to warn Jack that Kate was dangerous ("Tabula Rasa").
Resolved: Yes. Edward Mars finally begged Kate to euthanize him. She couldn't, but she asked Sawyer to. Sawyer missed, and Jack had to step in and finish the job.
Origin: They met on the day of the crash when Kate sewed up Jack's wound.
Since Then: The two collaborated on numerous activities in the camp, from playing golf to rescuing Charlie. Kate resisted Jack's early push to move to the caves, still hoping for rescue, The two spent time in the Swan together, and one day in the jungle Kate kissed Jack. The Others kidnapped the two of them, and Jack stumbled upon a video monitor of her and Sawyer after having had sex. He helped them escape the camp but stayed behind, and Kate returned to rescue him, only to find him doing fine. The camp split, and Kate initially stayed with Jack but later moved to the Barracks for a bit. Back on the beach, she helped Juliet remove his appendix. The the escaped the island together, and Jack testified as a character witness at her trial, which helped convince her mother not to testify against her. After discovering his relation to Aaron, Jack initially refused to continue seeing his nephew, but he changed his mind after the trial. Jack and Kate eventually moved in together and became engaged before breaking up. Jack eventually convinced her to return to the island, where she tried and failed to get him to operate on young Ben. His plan to reset time shocked her because it meant that it would erase their relationship, but she eventually gave in. In 2007, Jack chose to stay and protect the island, and Kate declared her love for him one final time before she kissed him goodbye. He died soon after. They reunited in the flash sideways and moved on with their friends.
Origin: Kate sees Juliet as a threat to Jack's affection
Prize: Jack's/Sawyer's affection
Fuel: Kate sees Jack with Juliet in the Barracks and is infuriated. ("The Man from Tallahassee") When Ben handcuffed Kate and Juliet together, they ran through the jungle, even getting into a fight. Juliet's refusal to answer questions did not help Kate trust her, especially after she lied about not having a key to unlock the handcuffs. Kate continued to grow jealous when Jack insists on bringing Juliet back to the beach with them. ("Left Behind") After Kate came to Jack to explain the camp's disapproval of Juliet's presence, Jack and Juliet's blatantly hinted at withholding a secret in front of Kate. ("The Brig") When both in the DHARMA Initiative, they both worked side-by-side in the motor pool. Seconds before Juliet's death, Kate tried her hardest to stop Juliet from falling, however, she was unsuccessful. ("The Incident, Part 2")
Resolved: Yes. Juliet died after the Incident and Kate has since accepted that she will never replace Juliet in Sawyer's affections.
Origin: Both were involved in the major happenings and decision making of the middle section survivors.
Since Then: Locke and Kate were originally very friendly with one another and became somewhat close as both of them were usually involved in the survivors various missions. Early on, Kate showed respect for Locke and even cared about his safety. When Locke decided to go into the hatch against Jack's wishes, Kate decided to accompany him to ensure he did not seriously hurt himself. When Kate was captured by The Others, Locke vouched for her saying she was a good person and someone reliable. Their friendship ended when Kate went against Locke's orders and broke Miles out of the boathouse. Locke banished Kate from his camp and the two wouldn't cross paths on the island again. When Locke visited Kate off the island she was very stand offish with him and would later tell Jack that she believed he was lying about the survivors they left being in danger. When Locke died, Kate showed no remorse and was appauled when Jack asked if she would go to his funeral. Despite everything she would later insinuate that Locke was indeed "one of them" when she referred to the Man in Black as not being John to Claire.
Origin: The Man in Black, in his smoke monster form, chased Kate through the jungle on her first day on the island.
Since Then: Kate met him again in his monster form on several other occasions, including after she gathered dynamite from the Black Rock and while she was handcuffed with Juliet. She met him again years later after he took Locke's form, and he tried to gain her sympathies, talking of his "crazy" Mother. Kate tried shooting him after he killed Sun, Sayid and Jin, and she later succeeded.
Since Then: The two shared Lost's first kiss in a scene where Sawyer demands a kiss in order to tell her where Shannon's inhalers are. She nurtured him through illness and the two bonded during many playful encounters. When both are captured by the Others, they bonded even more during their time working together in the rock quarry. During a beating while caged together on Hydra Island, Pickett demanded to know whether Kate loved Sawyer and under his threat to kill Sawyer she responded that she did. They made love in the cages. Sawyer's refusal to help rescue Jack created friction between them, but she went back to the Others for Jack, nonetheless. As Jack, Sayid, Hurley, Sawyer, and Kate leave the island on the chopper, Sawyer whispered something in Kate's ear, to her confusion. He kisses her and jumps off the chopper and into the ocean. Prior to the Oceanic 6's return to the island, Sawyer tells Horace that he had a "thing for this girl once", but after three years, can barely remember her face. However, upon seeing Kate, he is awash with nostalgia, but it is short-lived as he reminds a worried Juliet that "nothing's changed", and that he's with her [Juliet]. After a young Ben gets shot by Sayid, Kate and Sawyer attempt to save his life by bringing Ben to the Others. After Juliet's death, Sawyer leaves the main group, choosing to go at it alone. Kate, worried for his well-being, follows him back to the Barracks. She apologizes for Juliet's death, and starts to blame herself for the death by returning to the island.
Origin: Kate accompanied Sayid on his trip to higher ground. They heard the distress call together.
Since Then: Kate and Sayid initially cooperated on plans to escape the island, which sometimes put them at odds with Jack, who tried to form a society. Sawyer commented on the two men's growing rivalry over Kate, but this triangle ended when Sayid exiled himself from camp. For the next few months, Kate and Sayid worked together occasionally on missions, such as an attempt to rescue Jack from the Others and a later trek to track Jack and Sawyer. The two escaped the island together and apparently lost touch. They returned to the island and didn't interact before Sayid was shot. The Temple Others later drowned Sayid, and Kate had to tell Jack to stop trying CPR on him. Kate and Sayid both followed the Man in Black for some time, and Sayid did nothing while Claire tried to kill her.
Origin: Kate was attending Sun's garden with Sun and talking about herself thinking that Sun didn't understand English. When Sun gave a smirk, Kate claimed Sun understood her. Soon after Sun admitted to Kate about speaking English.
Since Then: Kate later convinced Sun to poison Jin to prevent him from going on the raft. However, Sun accidentally poisoned Michael instead. Kate and Sun had conversations about men and relationships such as in ...and Found when they found Sun's lost wedding ring. Sun confided in Kate when she believed herself pregnant. Kate helped Sun escape the island, though this meant leaving Jin behind to die on the freighter. Back in civilization, Sun returned to Korea while Kate's parole terms confined her to Los Angeles. They met again some years later when Sun came to LA on business. Kate stayed with her while she was fleeing a lawyer who was investigating her. Sun babysat Aaron and lent Kate a change of clothes.
Since Then: While on the run, Kate appeared at Tom's home, which he shared with his wife and son. They drove out to a spot they used to come to as children, dug up their time capsule, which included Tom's toy airplane, and the two shared a kiss. The next day, Tom helped Kate gain access to see her mother one last time, but when Diane reacted violently upon seeing her daughter, Kate attempted to make a quick escape. Tom chose to accompany Kate, and was killed in the crossfire by a police bullet during the car chase. Kate's most prized possession is the toy plane.