It is expected Meghan’s sister-in-law to be, Kate, will play a major role in the celebrations before the US divorcee ties the knot with Prince Harry at Windsor Castle in May. 

The women have grown closer since Harry introduced his fiancée to his brother Prince William and Kate in January 2017. 

And Meghan said Kate has been "wonderful" as she praised the Duchess of Cambridge in a TV interview shortly after the engagement was announced. 

Tennis star Serena Williams could also be on the hen guestlist of celeb friends Meghan Markle made when she rocked to fame in US drama Suits. 

PRINCE HARRY'S STAG DO PLANS 

Serena, who recently married Reddit co-founder Alexis Ohanian, was described as a “confidante” of Meghan's after the pair met at a charity football game in 2015. 

Meghan, 36, watched Serena at Wimbledon in 2016 and has previously supported her during New York Fashion week. 

Commenting on her friend, Meghan said: “She quickly became a confidante I would text when I was travelling, the friend I would rally around for her tennis matches, and the down-to-earth chick I was able to grab lunch with a couple of weeks ago in Toronto.”

The princess-to-be is also said to be close to Star Wars actress Janina Gavankar and the pair have known each other for 15 years. 

Meghan previously wrote on a picture of herself and Ms Gavankar: “Couldn't be prouder of how far we've come, and couldn't be more grateful for being able to share every step of it with you #imean #actorlife #grateful #friends (wait! @Janina I just did the math - did we become friends 15 years ago?!? Whoa.” 

Former Made in Chelsea star Millie Mackintosh could also make the grade after the pair spent a relaxing weekend away in Soho Farmhouse last year. 

Meghan took to Instagram writing: “The best afternoon with Millie Mackintosh. So proud of you darling.” 

Meanwhile, cast members from the Suits are likely to celebrate the upcoming Royal Wedding despite Meghan announcing she was leaving the US drama. 

The 36-year-old is said to be very close to former co-star Abigail Spencer. 

When asked why Prince Harry fell for Meghan during an interview with Vanity Fair, Ms Spencer said: "She’s got warm elegance, though her style is hard to pin down. It’s classy and timeless. 

“When you’re talking to her, you feel like you’re the only person on the planet. And it’s just wonderful to see her so in love.”

And Meghan’s “forever girl crush” Amanda Schull could also jet away with Meghan on a girly break before she marries Harry, 33, with the pair co-starring together in Suits since 2013. 

Meghan revealed she has been “in love” with Ms Schull since she starred in Centre Stage back in 2000. 

Rumoured to be the woman who first introduced Prince Harry to Meghan, Misha Nonoo is also a dear friend of the bride-to-be. 

The mystery matchmaker and fashion designer was previously married to Alexander Gilkes, an old Etonian and friend of Harry's. 

Canadian stylist, Jessica Mulroney, also counts herself as one of Meghan’s best friends and will probably join the US actress down the aisle as a bridesmaid. 

With an eye for fashion, Ms Mulroney is expected to help the bride-to-be when she chooses the perfect dress for her big day. 

And Meghan acted as maid of honour herself for her best friend Lindsay Roth when she organised trip away to Greece. 

The group of girls visited Hydra, in Greece, and spent a few days relaxing before the wedding.

The pair have been friends since their first year in university at Northwestern University. 

Ms Roth once said: “We’re the kind of friends who can be 3,000 miles away and still be talking about or thinking the same thing, and even texting each other the same thing at the same time miles away.” 

A controversial guest on the hen do list could be Meghan’s half-sister Samantha Grant who previously described Prince Harry’s future wife as a “shallow social climber”. 

But Meghan could be under pressure to prove her family are close and chose to invite her outspoken sibling. 

In an attempt to patch things up, Ms Grant has since reacted to the engagement news by saying she is “so happy” for Meghan - her half sister from her father Thomas Markle’s first marriage. 

Meghan revealed she has been “in love” with Ms Schull since she starred in Centre Stage back in 2000. 

Rumoured to be the woman who first introduced Prince Harry to Meghan, Misha Nonoo is also a dear friend of the bride-to-be. 

The mystery matchmaker and fashion designer was previously married to Alexander Gilkes, an old Etonian and friend of Harry's. 

Canadian stylist, Jessica Mulroney, also counts herself as one of Meghan’s best friends and will probably join the US actress down the aisle as a bridesmaid. 

With an eye for fashion, Ms Mulroney is expected to help the bride-to-be when she chooses the perfect dress for her big day. 

And Meghan acted as maid of honour herself for her best friend Lindsay Roth when she organised trip away to Greece. 

The group of girls visited Hydra, in Greece, and spent a few days relaxing before the wedding.

The pair have been friends since their first year in university at Northwestern University. 

Ms Roth once said: “We’re the kind of friends who can be 3,000 miles away and still be talking about or thinking the same thing, and even texting each other the same thing at the same time miles away.” 

A controversial guest on the hen do list could be Meghan’s half-sister Samantha Grant who previously described Prince Harry’s future wife as a “shallow social climber”. 

But Meghan could be under pressure to prove her family are close and chose to invite her outspoken sibling. 

In an attempt to patch things up, Ms Grant has since reacted to the engagement news by saying she is “so happy” for Meghan - her half sister from her father Thomas Markle’s first marriage.