Haters gonna hate, and that includes Samantha Markle, half-sister of the the Duchess of Sussex.

If it’s slipped your mind, Meghan Markle’s estranged relative didn’t get an invitation to the royal wedding and it has everything to do with the fact that, from the get go, she’s been extremely unsupportive of Meghan and Prince Harry’s relationship.

To add fuel to the fire, their father, Thomas Markle, hasn’t stopped speaking about his relationship with Meghan to the press, saying she looks “terrified” during public appearances and lashing out over the fact that the newlyweds haven't spoken to him. (He notoriously missed the wedding after undergoing heart surgery the week before the nuptials.)

Now, Samantha has once again lost her cool, taking to Twitter to drag Meghan for paying respect to Nelson Mandela, not their father, in London earlier this week.

Meghan Markle Samantha Grant
Credit: Splash News

“How about you pay tribute to your own father?! Enough is enough. Act like a humanitarian act like a woman! If our father dies I’m holding you responsible, Meg! @KensingtonRoyal” Samantha wrote, according to screenshots obtained by Cosmopolitan and the Daily Mail. Yes, you read that right. Samantha essentially threatened to blame her half-sister for their father’s death should he pass away. Yikes.

The rant didn’t end there. Samantha went on to defend her father and call out Meghan for “ignoring” him. “Glad you have so much time to gallivant around paying tribute to others while ignoring your own father!" she wrote. "How cold can you be and look in the mirror? Harry? I guess I was right. My father is not an embarrassment for loving his daughter! The Royals are an embarrassment for being so cold. You should be ashamed of yourselves @KensingtonRoyal.”

The palace could worry about Samantha, considering she’s reportedly working on a tell-all memoir (which was initially titled The Diary of Princess Pushy’s Sister, but has since been renamed to A Tale of Two Sisters), but with Donald Trump meetings and questions about whether the family did or did not snub Mr. President, it sounds like they’ve got bigger fish to fry.