Meghan Markle's half-sister Samantha has confirmed their father Thomas recently suffered a heart attack.

Thomas Markle Sr. had been due to walk the Suits actress down the aisle for her wedding to Prince Harry at St. George's Chapel in Windsor Castle, England on Saturday (19May18), but he told TMZ.com on Monday night that he had withdrawn from the ceremony due to health reasons, as he suffered a heart attack on 8 May.

His daughter Samantha confirmed the news on Good Morning Britain on Tuesday, and blamed the attack on the stress he has been under in the run-up to the wedding.

"He was really having heart pains and suffered a heart attack. It was an unbelievable amount of stress - by his report they were stabilising him," she said. "I think he wants to go to the hospital and get checked out. I don’t know as of today what his plans are, but there’s a very real concern, I wanted to see him go (to the wedding), I didn’t want him deprived of that. But clearly the priority should be whether or not it’s safe for him to do that."

Her comments confirmed a new report on TMZ suggesting Thomas, who checked out of a Mexico hospital over the weekend, wanted to go back to hospital because he fears he's on the verge of another heart attack. He claims he's experiencing serious chest pains which has been triggered by emotional distress, largely from Samantha's presence in the media.

"I've been popping Valium for the pain, especially when I hear about my oldest daughter," he said. He also confirmed he hadn't heard from Meghan since announcing he wouldn't give her away, and said he thought his ex-wife Doria Ragland should do it instead.

During her intense interview, in which co-host Piers Morgan called her a "vulture", Samantha said her dad is "quite depressed" over the "inaccurate" depiction of him in the media, particularly since it emerged he staged paparazzi shots showing himself preparing for the wedding, an idea Samantha claims was her responsibility.

She also alleged Thomas was being hounded by the press in an "atrocious and intrusive and highly unethical" manner, seemingly referring to Princess Diana's 1997 death, in a car crash, when she said, "He calls me panicking on the freeway when he’s in a dangerous situation being followed by seven or eight cars, I think there have been examples in history of how dangerous that can be."

A Kensington Palace spokesperson said in a statement on Monday, "This is a deeply personal moment for Ms Markle in the days before her wedding. She and Prince Harry ask again for understanding and respect to be extended to Mr Markle in this difficult situation."

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