Meghan Markle's half-brother, Thomas Jr., is the latest member of the former actress' extended family to come forward after failing to receive an invitation to her wedding to Prince Harry in Windsor on May 19.
In an explosive new interview, the 51-year-old said he was "deeply hurt" by the snub before accusing the bride-to-be of acting "phony" and having "forgotten her roots."
"Meg likes to portray herself as a humanitarian, a people's person and a charitable person but she is none of those things to her family," he told the Daily Mirror. "She is giving the greatest performance of her life. She is acting phony. Once she got into Hollywood she turned into a different person. She's clearly forgotten her roots and her family."
He added: "There's a whole different side of her that has started to surface and it's ugly to see."
Thomas, who was 14 when his half-sister was born, mused that the bride-to-be could, in actual fact, find her "normal" family embarrassing.
"Maybe the normal American family she has is embarrassing to her because we're not producers and executive producers," he said.
He then took aim at comparisons that have been made between Meghan and Harry's mother, the late Princess Diana.
"I've read that Meg wants to be like Diana. Diana was worshipped by everyone in the world. She was loved for the right reasons," he said. "That's what Meg wants, but I don't think that's going to happen. She's not genuine like Diana."
It follows a similar outburst from the royal-to-be's half-sister, Samantha Grant.
The mother-of-two, who has multiple sclerosis and has been wheelchair-bound for more than 10 years, recently took to social media to criticise the bride-to-be for inviting "more than 1000 complete strangers" when members of her own family didn't make make the cut.
WATCH: Samantha backtracks on earlier comments made about her half-sister. Post continues...
"At issue is not a matter of closeness as more than 1000 complete strangers are invited. Family is family. I have an uncle I have only seen once but I would never say he is not family because we are not close," she wrote on Twitter. "Humanitarians move forward with love and kindness especially to Family."
She added: "Smoke and mirrors cannot hide the elephant in the room. Out of respect, tradition, and humanitarianism, the #Markles should be invited if 2000 complete strangers are invited. Our uncle who got her the internship, brother, me, best friend of 30 years Nikki Priddy, nephews. Fact."
Although nothing has been confirmed in an official capacity, there's speculation Meghan will be walked down the aisle in St. George's Chapel next month by either her mother or father.
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