Origin: Claire found herself unexpectedly pregnant with Aaron after a relationship with Thomas.
Since Then: When Thomas broke up with her, Claire tried to give her baby up for adoption. A fake psychic warned her against this but later advised her to fly on Flight 815 to find a specific Los Angeles couple. Claire gave birth on the island. A mad woman kidnapped Aaron, and he later suffered from a fever that worried her. The Oceanic 6 escaped the island with Aaron, but Claire stayed behind and spent the next several years pining after her child. She eventually escaped the island, planning to raise Aaron with Kate. In her afterlife, giving birth to Aaron woke Claire up.
Since Then: The two had a poor relationship. Claire at one point screamed that she hated Carole and wished she weren't her mother. The screaming made Claire crash the car she was driving, sending Carole into a coma. Doctors said she would never recover, but Claire didn't give up hope and regularly visited her mother. The two presumably reunited once Claire escaped the island years later.
Origin: Charlie and Claire developed a bond throughout most of the first season, as Charlie reached out to Claire as a friend.
Since Then: However, as Claire starts to trust Charlie and lean on him, she is kidnapped by Ethan who also attempts to murder Charlie by hanging him from a large banyan tree. When Claire returns she does not remember the events or the people she has met since the day of the crash. Charlie reaches out to her again to gain her trust back. After Aaron is born, Charlie voluntarily assumes the role of 'daddy' to Claire's 'mommy', a bit to Claire's surprise. But when Claire discovers Charlie is/was a heroin addict, she gets angry at for lying to her and the situation only grows worse when Charlie, prompted by dreams that he interprets as prophecies, tries to kidnap Aaron to baptize him in the ocean. After this incident, Locke decides to watch over Claire while Charlie looks on jealously. Things seem to be on a standstill for a while until Charlie returns from the the Swan Station discharge, and Claire looks genuinely happy to see him alive and well. That evening, she kisses him. However, once Charlie discovers that Desmond's clairvoyant flashes all revolve around his own death, he volunteers himself to swim down to the Looking Glass station to un-jam incoming transmissions. Realizing his doomed fate, he says goodbye to Claire but doesn't tell her that he doesn't plan to return. During his heroic act, he drowns. Claire is devastated upon hearing of Charlie's death.
Origin: Christian fathered Claire after a fling with her mother.
Since Then: Christian visited Claire regularly when she was young, reading and singing to her. Her mother later discouraged his visits. Christian returned to Australia years later to pay Claire's mother's hospital bills, and he finally revealed himself to his daughter. He encouraged her to let her mother die. On the island, the Man in Black first contacted her using Christian's form.
Prize: Motherhood. Danielle's baby daughter was kidnapped sixteen years before, and she was jealous of Claire's new happiness.
Fuel: Danielle has scars on her arm from Claire scratching her during a struggle. Claire believed that Danielle was trying to take her back to the Others, but Claire was heavily drugged, with her memory impaired, and she misinterpreted the situation ("Maternity Leave").
Resolved: Yes. Once Claire regained her memory, she realized Danielle was trying to save her from drawing Ethan's attention to herself in the jungle. Claire told Danielle about having met Alex in the Staff, and this strengthened a bond between them.
Origin: On reurning from his failed sail from the Island, Desmond talked to Claire on the beach about her baby its father.
Since Then: Desmond later moved into the beach camp. He built a lightning rod above Claire's tent, saving it from a lightning strike, and he later saved her from drowning in the ocean. Some time later, he interrupted her attempts at catching a bird for a rescue message, but he later caught one for her himself. He mentioned Claire to Charlie to try to dissuade him from killing himself in the Looking Glass, but to no avail.
Desmond escaped the Island, and he later returned and left again without seeing Claire. The two may or may not have ever met again when alive. After death though, in a flash sideways, Desmond approached Claire in LA airport, offering her a ride and suggesting her unborn child was a boy. He later approached her again and brought her to his lawyer to introduce her to Jack. This didn't wake her up, but she ended up at a concert, and Desmond brought Kate to her table. Soon after she gave birth to Aaron and woke up, Desmond appeared and told them the next steps toward moving on.
Origin: Ethan noticed a pregnant Claire in the beach camp. According to Ethan, his own wife had died in childbirth, and Claire's impending danger affected him.
Since Then: Ethan appears to have approached Claire repeatedly at night with a needle. When Hurley began comparing survivor names against the plane manifest, Ethan realized he had little time to act and quickly kidnapped Claire, against Ben's instructions. He took Claire to the Staff medical station where he took care of her but kept her drugged. He showed her a potential nursery for Claire's baby, which delighted her. Before he could operate on Claire, delivering her child by Caesarean just as he had been, she escaped. He approached Charlie, demanding her return, and he tried to abduct her again - falling into the survivors' trap. Charlie killed him right after.
After death, Claire imagined herself pregnant again and found Ethan as her obstetrician. Ethan offered herdrugs to suppress her labor, ironically now reluctant to "stick her with needles".
Origin: Jin offered Claire some seafood after the crash of Flight 815.
Since Then: Jin showed concern for Claire after she returned from Ethan. Jin later discovered Claire about to give birth. He ran to Jack to deliver the news then returned to Claire and helped deliver the baby. He and Sun later occasionally babysat Aaron for Claire. Jin also helped her fish when she tried to trap seagulls. Claire saved Jin years later from Others who planned to shoot him. He lied to her on Aaron's whereabouts to protect Kate - and himself.
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.
Origin: Claire and Locke started spending time together when Locke inlisted her help in building a cradle for Aaron.
Since Then: Locke served as a type of father figure to Claire, his knowledge of babies made him a big help to her as she raised Aaron. Claire would often go to Locke for advice on certain things. Locke would come to Claire's aid when Charlie began acting strangely, he even moved his tent next to Claires so she would feel safe. When the group split up Claire went with John's group (because of Charlie's message). Locke would last see Claire in The Cabin, confused by her strange behavior Locke decided not to tell anyone of her whereabouts.
Origin: Claire had heard about the monster, but she didn't see it till it's arrival at the Barracks. It then attacked the men who'd just been firing rockets at her house.
Since Then: The following evening, the Man in Black approached Claire as her father, Christian, when she was in the jungle. She left Aaron behind and followed him to Jacob's cabin.
He kept her company over the next few years; the Others referred to this as claiming her and infecting her with the sickness. Claire changed considerably during this time, becoming more aggressive and less stable. The Man in Black told her that the Others had taken Aaron, justifying this by saying the hatred helped sustain her. He eventually began appearing to her simply as her "friend" rather than as her father, and Claire realized that he had been merely impersonating Christian earlier.
Once Jacob died and the candidates arrived on the Island, the Man sent Claire to warn the Temple of his arrival. Kate joined his group soon afterward, and he separated the two when Claire attacked, slapping Claire to quiet her. Claire learned she was not a candidate and feared he did not need her, but the Man in Black assured her that he did. Kate convinced her nonetheless to try to escape with her, an act that the Man seemed to later forgive. When the candidates boarded a trapped submarine, the Man held Claire back. But he abandoned her soon after to kill the sub's survivors.
Origin: Claire was in a relationship with Thomas when she discovered that she was pregnant.
Since Then: When she told Thomas the news he seemed excited and convinced her to keep the baby, promising he would be there for her. Encouraged by this, Claire moved in with Thomas. However, it wasn't long before Thomas started feeling doubt about the whole situation and accused her of not taking the 'pill' to avoid her condition. They argue, and Thomas breaks up with her.