Meghan Markle Says Her Father Lied to Her About Talking to the Press: 'Hard for Me to Reconcile'

Meghan Markle is opening up for the first time about her complicated relationship with her father, Thomas Markle, and estranged half-sister, Samantha Markle.

In a new clip from her sit-down interview with Oprah Winfrey on CBS Sunday (her first since her engagement to Prince Harry in 2017), the Duchess of Sussex, 39, addressed the tension within her family.

For more on Prince Harry and Meghan Markle's interview with Oprah, listen below to the episode of PEOPLE Every Day.

Asked by Oprah, 67, whether it "felt like betrayal" when she learned her dad "was working with the tabloids" in staging paparazzi photos, Meghan said, "The tabloids had apparently known [her father's location] for a month or so and decided to hold until the Sunday before our wedding because they wanted to create drama."

"We called my dad and I asked him [about staging the photos] he said, 'No, absolutely not,' " the Duchess continued in the Monday, CBS This Morning clip. "I said, 'The institution has never intervened [on] anything for us, but they can try to go in and kill this story. But if they do this once, we're not gonna be able to use that same leverage to protect our own kids one day.' "

"I said, 'I just need you to tell me and if you tell me the truth, we can help,' and he wasn't able to do that," Meghan said. "And that, for me, has really resonated, especially now as a mother."

Meghan — who shares 22-month-old son Archie Harrison with Harry, 36, and is expecting the couple's second child, a baby girl — added, "I look at Archie, I think about this child [on the way], and I genuinely can't imagine doing anything to intentionally cause pain to my child. I can't imagine it. So it's hard for me to reconcile that."

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Samantha — Thomas' daughter from his first marriage — has been outspoken since Meghan first stepped onto the royal stage. Neither Samantha nor Thomas, 76, attended Meghan's wedding in May 2018.

Addressing Meghan and Samantha's relationship, a source close to the Duchess previously told PEOPLE that "Meghan has no relationship with her half-siblings, nor has she ever had one."

In addition to writing a memoir titled The Diary of Princess Pushy's Sister, Samantha later took responsibility for arranging Thomas' staged paparazzi photos in the weeks leading up to the royal wedding — which Thomas admitted he lied to Harry about.

Samantha went on to confess that she had been "cashing in" on Meghan's fame.

"Let's face it — we all have to survive. Money makes the world go round, so if you want to call that cashing in, that's fine, but I think no one in media would refuse a paycheck for talking about the royal and, as a family, we're not subject to royal protocol," she told Good Morning Britain in July 2018.

RELATED VIDEO: Meghan Markle Reveals to Oprah the "Liberating" Feeling of Finally Being Able to Speak Freely

Of her relationship with Samantha today and how she feels about the book, Meghan told Oprah in Monday's video, "I think it'd be very hard to 'tell-all' when you don't know me."

"This is a very different situation than my dad — when you talk about betrayal, betrayal comes from someone that you have a relationship with, right? I don't feel comfortable talking about people that I really don't know," she continued.

"The last time I saw [Samantha] was [about] 19 years ago, and before that, 10 years [previously]," Meghan said. "She changed her last name back to Markle I think ... only when I started dating Harry. So I think that says enough."

The Duchess said earlier in the conversation that she "grew up as an only child" but wishes she "had siblings," and is now focused on giving her son that kind of relationship going forward.

"That's why I'm so excited to be pregnant — so that Archie has someone," Meghan added.

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Meghan and her father were recently involved in a privacy and copyright infringement case. The Duchess won her claim against the Mail on Sunday's publishers last month after a British judge granted summary judgment in her favor over five articles published in February 2019 that reproduced parts of the handwritten letter she sent her father following her wedding to Harry.

During the summary judgment hearing in January, Meghan's attorney, Justin Rushbrooke, argued that her letter to her father was "intrinsically private, personal and sensitive" and that printing extracts of it constituted "a triple-barrelled invasion of her privacy rights."

It was "a heartfelt plea from an anguished daughter to her father," Rushbrooke added.

In addition to attending Meghan and Harry's wedding at Windsor Castle, Oprah, 67, is also one of the couple's neighbors in their Montecito, California, neighborhood, where they moved this past summer.

The longtime television journalist is also teaming up with Harry for a mental health docuseries for Apple TV+. In a 2019 interview with podcast host and journalist Bryony Gordon, Harry said the series — which will premiere this spring — will unveil examples of "human spirit fighting back from the darkest places."