On the way back, she and Charlie are kidnapped by Ethan Rom (William Mapother).
Ethan went rogue and kidnapped Claire to further their research. In Claire's flashbacks about her time with him, Ethan is scolded by Tom for breaking their plans and bringing her in early. Ethan took matters into his own hands because they were about to discover he wasn't on the plane.
Is that not exactly what Ethan did to Claire? He kidnapped her to experiment on her pregnancy in order to better understand the ferility crisis effecting their ``tribe'' of Others which in turn effects the lineage and continuation of their community as they need more children to have more Others.
Claire survives the island's events. She endures kidnapping, psychological trauma, and temporary control by the Man in Black, becomes feral, attacks survivors while under that influence, but is alive and present at the end of Lost, freed from his control.
In the season one finale, set 43 days after the plane crash, Rousseau arrives on the beach and warns everyone that the Others are coming. After Claire gives birth to her son Aaron, Rousseau steals him and intends to swap him for her own child. When the Others do not come, Rousseau reluctantly returns him to Sayid.
Both Rousseau and Karl were shot dead. Her body was discovered by Miles as he, Sawyer, and Claire were going back to the beach. In the afterlife, Danielle shared a happy, normal life with Alexandra, away from the Island.
Days 1–44 (Season 1)
A few days later, Claire went into labor with help from Charlie, Jin and, most of all, Kate. She gave birth successfully to a boy, but she remained worried in the days that followed that the Others would try to take him.
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.
However, Claire reveals that she is pregnant by Frank, which means that their child will receive the entire Underwood inheritance, leaving nothing for Doug.
Claire's madness is a direct influence from the smoke monster, her best bud for the remainder of the show. It's heavily insinuated that she, like Sayid, died and was brought back to life by the smoke monster.
Introduced in the first season as the main antagonist, Ethan is the surgeon for the antagonistic and mysterious group known as the "Others".
She tells Jack about her affair with his father and their daughter, Claire, causing Jack to finally realise his relation to Claire. Claire herself learned of this sometime during the three years she spent alone on the Island, as, upon Jack's return, she greeted him as "my brother".
In the books, it's a bit more clear that Master Raymond is a time traveler like Claire. In fact, it's hinted, or at least theorized, that he is one of the original time travelers and may even be an ancestor of Claire and Geillis Duncan (Lotte Verbeek), explaining why they can travel through the stones.
The sickness, or infection, is actually caused by the Monster. He infected Sayid via the pool, but he infected Rousseau's team via the tunnels. It's also widely accepted that Claire was infected, but it's not known how.
Despite not having raised Walt, Michael loved his son and cared for nothing else but his protection. This obsession led him to many conflicts with the other survivors (mainly Jin and Locke) to the point of betraying them and killing Ana Lucia and Libby.
The character disappeared for season 5 and returned in the last season, but let's look back at why that disappearance happened.
He definitely cheated. There's the argument between Claire and Frank when she mentions it and he says “I thought I'd be discreet.” There's also the part in Drums of Autumn when Claire is reflecting on her relationship with Frank and she again mentions his “late nights” etc.
Captain Randall very closely resembles his brother Alexander's 20th-century descendant, Frank Randall. The likeness is such that Claire Beauchamp mistakes Jack for her husband upon arriving in the past.
In season 3, when the Underwoods are President and First Lady of the United States, Claire's marriage to Frank begins to falter. She tires of being in a subordinate role to him, wanting to be "significant" in her own right, and decides that he is "not enough" for her.
The Others are infertile and cannot reproduce, so they kidnap children on the Island to continue their work. Assuming the magic box Ben alludes to in "The Man Behind the Curtain" does exist, it would help explain why the children were taken, why Walt was abducted, and why children are so seldom seen at the Barracks.
Before the Crash
When he suggests that Claire turn off her mother's life support, she is angry and leaves without learning his name. Years later, Claire becomes pregnant by her then-boyfriend, Thomas (Keir O'Donnell). He convinces her to keep the baby but leaves her a few months later.
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.
Claire (Caitríona Balfe) becomes deathly ill and many around her fear that they may lose her. From Season 6, Episode 6 'The World Turned Upside Down' - A dysentery epidemic spreads on the Ridge, and Claire falls deathly ill.
Kate decides to remain at the barracks, in an attempt to extract information from Miles. She arranges for him to speak to Ben, but is caught by Locke. She spends the night with Sawyer (although they did not have sex) and tells him that she is not pregnant.
The name Aaron comes from a Hebrew word meaning "bearer of martyrs". Sun asked Claire what it meant but Claire said she didn't know. The name could also derive from an Egyptian word, "Aha Rw", which means "warrior lion."