Meghan Markle's Half-Sister Will Star On This Season Of 'Celebrity Big Brother'

It's unclear what Samantha Markle has done to be famous, outside of having a famous half-sister, but she made clear that the purpose of her going on the show was not to "talk about Meghan."

According to a previous report by the Inquisitr, Samantha previously made a loud, threatening comment to her half-sister with regards to their father.

When Meghan and Harry stopped by the Nelson Mandela exhibition in London, England, Samantha took to her Twitter to lambast the duchess, claiming that she wasn't "acting like a real humanitarian" when it came to their father.

She then said that if their father, Thomas Sr., dies as a result of a heart attack -- since he's been claiming to have heart problems from the day Meghan married Harry -- Samantha is personally holding the duchess responsible for his demise.

But, of course, this could all also be publicity for Samantha's new book, In the Shadows of the Duchess. The book was originally supposed to be called The Diary of Princess Pushy's Sister, but that didn't go over well with the publisher.

For her part, Meghan Markle hasn't spoken to her half-sister in more than a decade, and she wasn't invited to the royal wedding, either.