Meghan Markle may have married the man of her dreams two months ago but their happy union is not smiled upon by everyone in her family as her older half-sister continues to speak out in criticism of the new Duchess of Sussex. 

Prince Harry and Meghan MarkleMeghan Markle's family have been vocal in the media since the start of her relationship with Prince Harry

Samantha Markle has been an ongoing presence in the media since her younger sibling announced her engagement to Prince Harry and her latest outburst has been one of the most brutal as she told the Duchess if their father died she would be to blame.

Drama surrounded Meghan’s father, Thomas Markle around the couple’s wedding day in May when he pulled out of walking her down the aisle just a few days before, citing health issues.

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Since then, Thomas, 74, has continued to speak to talk to the press, exclusively to America website TMZ and has said he will continue to talk to the media until his daughter has accepted him back into her life.

His eldest daughter, 53-year-old Samantha then launched into a Twitter tirade against the Duchess hours after Thomas spoke to TMZ again and took aim and Meghan and Harry’s appearance at the Nelson Mandela centenary exhibition in London.

She wrote: "How about you pay tribute to your own father?! Enough is enough. Act like a humanitarian, act like a woman. If our father dies, it's on you Meg.

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"Glad you have so much time to gallivant around paying tribute to others while ignoring your own father!

"How cold can you be and look in the mirror? Harry? I guess I was right."

Samantha has appeared on a number of chats shows and conducted various interviews about her sibling since her accession into the Royal limelight, despite not having seen her in a number of years.

The mother-of-three is also reported to be writing a book about ‘living in the shadow of a Duchess’.