Congrats are in order for Prince Harry and Meghan Markle! The new Duke and Duchess of Sussex said "I will" in front of roughly 600 people during their Windsor Castle wedding on May 19, but Meghan's estranged half-siblings weren't among those lucky guests. Thomas Markle Jr. and Samantha Grant (who goes by Samantha Markle on social media) are the children of Thomas Markle Sr., Meghan's father, from a previous marriage of his. Thomas Jr. is a window fitter from Oregon, Samantha is a Florida woman living with multiple sclerosis, and both sibs have aired a lot of thoughts about Meghan leading up to the ceremony.

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As In Touch reported, Thomas Jr. wrote a letter to Prince Harry, warning him he was about to make "the biggest mistake in royal wedding history" and saying Meghan is a "jaded, shallow, conceited woman that will make a joke of you and the royal family heritage."

He added, "You would think that a royal wedding would bring a torn family closer together, but I guess we're all distant family to Meg. Meghan is still my sister. She is family. So whatever happens is up to her. Whether she wants to forget knowing me or the rest of her family, family comes first."

Just months prior, however, the 51-year was striking a more conciliatory tone — as he issued a mea culpa in the wake of his January arrest for menacing, pointing a firearm at another person, and unlawful use of a weapon in an alleged altercation with his girlfriend. "Everyone makes mistakes," he said, per The Sun. "This time I made a bad one. But we all do. If I may say so, Prince Harry has made a few in his time and learnt from them. I just need the same chance. I want to tell Meghan I am truly sorry from the bottom of my heart. The last thing I would ever want to do is put a black mark on her situation with the royals."

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Meanwhile, Samantha — who has called Thomas Jr. a "lowlife" and a "lying thief" — had a message for Prince Harry, too, prior to the big day. On Twitter, Samantha told him to "man up" and stop "allowing Meg to ignore the Markles." She also dissed Meghan for "inviting thousands of complete strangers to her wedding and ignoring her family." And she argued that the royal couple should arrange a "tented area with steak dinner, music, jobs corps, and housing representatives" at Windsor during the royal wedding.

Plus, Samantha promised to write a tell-all book "complete with facts and photos," a book she originally titled The Diary of Princess Pushy's Sister before naming it A Tale of Two Sisters. She insisted it wasn't a takedown of "Princess Pushy," though, saying it "deals with my biracial family in a candid, warm, personal, and socially-important way." (Her estranged mother, however, told the Daily Star everything Samantha has said about Meghan "is a lie.")

The 53-year-old added that she didn't receive an invitation to the royal wedding, but considering she was injured in a car accident earlier this week, it seems like she wouldn't have been able to attend anyway!

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