In a series of tweets over the weekend, she said “I couldn’t help but let it slip!” as she revealed that there would be a second part of ‘In the Shadows of The Duchess,’ coming out in June.
The first is set to coincide with the arrival of Meghan and Harry’s first child, due in April.
Ms Markle, 54, appeared to hint that there would be unseen photos in the second publication.
She tweeted: “And you will love some of the pictures in my book also to refute any of your nasty troll gossip that we did not have a life together.”
“I’m very much your sister and if you don’t like it too bad.
“Bring it on .. I think everyone should take a lie detector test.”
Last year, Samantha spoke to Daily Star Online about the tell-all book: “In The Shadows Of The Duchess covers everything… the world does not know truth total truth… (I’m) holding nothing back!
“From lullabies to lies.. it’s all they’re [sic] in my book.”
“[Samantha] has filmed a reality show by Endemol, so you know it’s going to be a big one.”
It’s the latest in the drama that has surrounded Meghan’s paternal side of her family.
The Duchess has been estranged from her half siblings Samantha and Thomas Markle Jr. for years. Both have hit out at Meghan negatively on social media and in the press and neither reportedly received invitations to her and Harry’s royal wedding in May 2018.
Samantha, who shares the same father Thomas Markle Sr, with Meghan, appeared on the Jeremy Vine on 5 show to apologise to her half sister. But she has continued to criticise Meghan on social media since then.
The Duchess of Sussex reportedly has not had any contact with her dad Thomas Markle Sr, since before her wedding, when he was caught staging paparazzi photos for money. He subsequently pulled out of walking his daughter down the aisle, due to health problems.
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