Samantha Markle has claimed her half-sister Meghan Markle won't reunite with her estranged family unless she has "a motive".
The 58-year-old went on a scathing rant about Meghan as she accused the Duchess of Sussex of lacking "empathy, remorse, or shame".
Meghan, 41, has a strained relationship with her father's side of the family and previously admitted she hasn't seen Samantha in more than a decade.
Samantha has now sat down with her father Thomas Markle Snr and brother Thomas Markle Jnr for a world exclusive interview about their relationship with Meghan.
When asked if she would like to talk to her half-sister and "put all that water under the bridge", Samantha said it is unlikely to happen.
"I don't think she would do it without a motive.
"I don't think she's capable of empathy, remorse, or shame. I don't think she could feel enough to apologise," she told Channel 7's Liam Bartlett.
The broadcaster also asked if Meghan's marriage to Prince Harry had "improved her behaviour", but Samantha said, "It's made it worse".
Meghan and Harry tied the knot in 218, but the only close relative at her wedding was her mother Doria Ragland.
Meghan's father did not attend after he became the centre of a scandal when he was caught staging paparazzi pictures of himself in exchange for payment.
Speaking about Harry and Meghan's relationship, Samantha claimed: "I think it's made it worse because I think he has the personality profile that perfectly enables someone who is an alleged narcissist."
She added: "I think he's enabled her and I don't think they're improving each other's lives. I think it's a toxic relationship because they're co-dependent."
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Despite Samantha's harsh comments about her half-sister and her relationship with the Duke of Sussex, her own mother, Roslyn has suggested that Samantha is simply "jealous" of Meghan and has been for years.
"I am very serious when I say she has dogged on Meghan forever," she told the Daily Mail in 2017. "She has never liked Meghan and she's always been jealous of her.
"She's just doing it because she's got nothing better to do and it's what she's always done. It's why nobody talks to her and hasn't for a long, long time. Leave Meghan alone already – it's ridiculous."
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