Kaya and her mum parted ways for good in The Nest series finale tonight (April 13).
Seven years ago, the pair disowned each other after the teen was jailed for murder when she was just 11-years-old.
But their complicated history has never been fully explored – until now.
Although the pair have tried to put the past them, the mother and daughter find out the hard way that old habits die hard.
Who is Kaya's mum in The Nest?
Kaya previously said her mother didn't raise her as she had been violently killed.
But that wasn't true.
Siobhan Gordon (Bridget Jones star Shirley Henderson) is still very much alive and did look after her before she was sent to prison.
READ MORE: Kaya's true identity in The Nest explained
Kaya disowned her mother after she was jailed for murder as a young girl.
Although she was technically responsible for the death of a pregnant woman and her baby, the truth is more complicated than that.
The pregnant woman was actually her auntie Neve.
She died after Kaya tried to intervene between an argument that broke our between Siobhan and Neve.
During the heated exchange, Siobhan pulled out a knife.
As 11-year-old Kaya grabbed it off of her, the blade accidentally went into Siobhan's leg, severing an artery.
While Siobhan blames her daughter and brands her actions evil, Kaya explains that in therapy, she came to understand that what happened was an accident and she was just a child.
In tonight's finale, the pair discuss what happened and decide it's best to cut ties once more.
Why is Kaya's mum afraid of her?
Opening up about her character, Shirley told the Sunday Post: "Siobhan is steeped in memories and haunted by things that have happened to her. There are years of discomfort. She has had a lot of problems and physical difficulties.”
"Siobhan has a combination of mental health and physical health problems, having lived and gone through all sorts of things. She over-thinks, she spends a lot of time on her own and her mind goes round in circles. She takes a step to try to help herself at the beginning that either helps or destroys her."
Confirming Siobhan and Kaya's reunion, Shirley added: "[They] have a history with each other and as the story unfolds they wind their way back to each other. It’s strong, difficult, complex, wonderful and at moments very scary."
What time is The Nest on?
The Nest series finale is on BBC One tonight (April 13) at 9pm.
If you miss an episode, you can catch up on BBC iPlayer.
In total, there are five episodes of The Nest.
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