How Meghan Markle's family will be involved in the royal wedding

Meghan Markle and Prince Harry's royal wedding preparations are underway -- including what role the bride-to-be's family will play!

A source tells ET that Meghan wants both her parents to be involved in her May 19 nuptials.

"Meghan asked her father to walk her down the aisle,” the source says. "She does want him included and she wants to uphold tradition."

Meghan's father, Thomas Markle -- a 73-year-old retired lighting director who was divorced from Meghan's mother, Doria Radlan, in 1988 -- has, in recent years, moved to the quiet seaside town of Rosarito, Mexico, and has remained relatively off-the-grid.

As for Meghan's mother, the two appear to have close relationship and are frequently photographed together. The source says Radlan "will also have a significant role that day."

Meghan gushed about her mother in a recent interview with Glamour. "We can just have so much fun together, and yet, I'll still find so much solace in her support," she said. "That duality coexists the same way it would in a best friend."

While her mother and father will be there, a source tells ET that one of her Meghan's family members will not be getting an invite -- the 36-year-old actress' half-sister, Samantha Grant.

"Samantha is a wild card," the source says, also acknowledging the two have had a "strained" relationship in the past. "She has no filter and she’s not afraid of the repercussions of speaking her mind."

The source explains that Meghan is able to invite whomever she wishes, and the guest list will include most of her family members and friends.

On Thursday, Meghan and Harry released a series of intimate engagement photos!

When the couple announced the happy news, Meghan's parents issued a joint statement, saying, "We are incredibly happy for Meghan and Harry. Our daughter has always been a kind and loving person. To see her union with Harry, who shares the same qualities, is a source of great joy for us as parents. We wish them a lifetime of happiness and are very excited for their future together."

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