He has been cut off the guest list for her big day it is now being reported.
And he will have to settle watching the event from his home in Oregon as Meghan exchanges vows 8,000 miles away with Harry in Windsor Castle, England.
A source revealed: "Tom did not receive an invite.
"I think it is because he just can't seem to keep his mouth shut.
"If he would quit talking to the media, Meghan would probably be more into the idea of inviting him.
"There are a few people who like to say stuff to have them in the limelight."
Thomas – who shares the same biological father as Meghan – slammed her in a recent magazine interview.
His lawyer reportedly claimed Meghan denied knowing Tom when he asked for help on how to deal with the press.
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Tom slammed his half-sister's response as "harsh" and a "slap in the face", and admitted they haven't been in touch since Meghan moved to Toronto, Canada in 2011 to start her role on Suits.
And it looks like she does not want him to attend her wedding day either.
It is expected that two members of Meghan's family will attend the event – her dad Thomas Markle Senior and mum Doria Radlan.
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