Claire eventually realizes that Malva is lying because she knows her husband well enough. Tom seems to question Malva's story. You can see it in his face that he's trying to figure out if this story is true. And then there are the reactions at the funeral when Allan refuses to let Claire carry the baby's coffin out.
But things take a far more tragic turn when Claire discovers Malva lying in the Fraser garden, her throat slit. Claire desperately tries to save Malva's unborn child, cutting the baby from her womb, but it's too late.
Claire knows that she didn't have the same thing, but she can't get to the bottom of the cause. It's Tom who eventually finds out. Malva, before her death, tells him that she made them sick. She'd collected parts of the dead Sin Eater and poisoned Claire and Tom.
Claire decides there's one thing that shows Malva is lying in Outlander Season 6. After some thinking, Claire realizes that Jamie has to be telling the truth. He can't be the father of Malva's child, and it all comes down to who Jamie is fundamentally. Claire explains it in Outlander Season 6.
Tom later confesses to Malva's murder, although he did not do it; he tells Claire privately that he knew the girl was like her mother, a witch and a siren, luring men. He also tells her he found the remainder of Ephraim's bones in Malva's work basket, beating her for the truth.
Although Allan got away with murder, he later told Claire the truth at Malva's graveside and admitted to her raping and impregnating her. Additionally, Allan confirmed he took Malva's life because she was going to reveal the truth and he didn't want this.
After starting off the season fairly well, Claire ended it imprisoned for Malva's murder in a rat-infested jail in Wilmington, injured from being stoned, her hair chopped off, and no idea whether Jamie is dead or alive. Her only ally in Wilmington is Tom Christie, and he's a dubious ally at best.
The haircutting was part of the process. Malva wanted to make Claire undesirable. She wanted to make Jamie turn to her instead of to his wife. We can get a sense of that from the way Claire worried about Jamie seeing her with the short, jagged hair.
She's never seemed curious about the intimacies of a couple before. This suggests that she's up to something. Watching the two gives her information to use in the future.
Jamie denies having slept with her, but the damage to his and to Claire's reputation is done—and the bond between the Frasers and Malva is severed, until just a few weeks later, when Claire finds Malva murdered in the garden. “It's like the peak of the tragedy, and it's so visceral.
The killer is in fact Malva's brother, Allan Christie (Alexander Vlahos). He is also the father of her baby, having raped and abused Malva since she was a child. Malva had decided to tell the truth, which is why Allan killed her.
During Outlander Season 6, Episode 6, Claire's near-death experience was the least of her problems. Months later, the Christies came to the Frasers with news. Malva is pregnant and she claims that Jamie is the father.
Rather, Tom focused on the wickedness in Malva that needed to be beaten out of her. His ignorance and his bias meant that instead of protecting this young girl, he chose to think of her as evil. Because of everything she puts the Frasers through, Malva is one of the easiest Outlander characters to hate.
In the TV series, we get to see how Malva knows all about Jamie's scars. She spies on Claire and Jamie when they're in the barn, which is going to lead to all of his scars on show. The TV show gave us this scene so that it would clear up questions later on.
This is dysentery. Claire tells everyone that a contaminated water source most likely caused it, but after funeral upon funeral — the body count is high! — no one can seem to figure it out. And then Claire falls ill.
In November 1776, Allan comes to Malva's grave and confesses to Claire about raping his sister, that he was the father of Malva's child, and that he killed her because she was going to tell the truth.
However, while Malva is killed in May 1775 in the book's timeline, it isn't until November 1776 before her killer is revealed. Eventually, Claire finds Allan Christie by Malva's grave and he admits to having sexually abused his sister since she was a child and the unborn child was actually his.
Tom confesses to Malva's murder and tells Claire that the strange sickness he shared with Claire seen at the beginning of Outlander season 6, episode 6 was Malva's attempt to murder them both.
Why was Malva watching Claire and Jamie? She wanted to make sure Claire knew the truth, but Claire didn't let her into the house. Instead, her attacker—likely the real father of her baby—turned up and killed her before she could say anything to Claire.
Then there are times that they seem made up, but they do actually have a basis in the book storyline. During Outlander Season 6, Episode 5, we saw Malva cutting the fingers of the dead Sin Eater off.
Malva Christie might have only been introduced in Outlander Season 6, but she has a central role in the drama. The daughter of Tom Christie, she is both naive and sinister, and many Outlander fans have struggled to work out her true intentions.
In a shocking turn of events, Outlander season 6, episode 6 saw Claire's apprentice Malva accuse Jamie of infidelity, claiming her unborn child is Jamie's, but the aftermath forgets one critical detail from Outlander season 3.
Some think Jamie's spirit (but not his body) traveled to through time to guide Claire to him; others suggest Jamie had a near-death experience after the Battle of Culloden, and that's why his ghost is 25 when he appears to Frank.
Diana Gabaldon has confirmed there is no possibility that Jamie Fraser will time-travel into the future and live out his life at Lallybroch.
For now, though, it appears both Fergus and Marsali aren't time travellers with actors Lyle and Domboy addressing this in an Instagram live Q&A from earlier this year.