Here comes the bride!

Kate Middleton‘s younger sister, Pippa Middleton, is set to marry her handsome fiancé, James Matthews, on Saturday, May 20 — and now that her big day is less than 24 hours away, here’s everything we know about her wedding!

She has a gorgeous engagement ring.

According to [People](http://www.people.com/people/package/article/0,,2039522221019643,00.html)_, the 33-year-old socialite’s Art Deco ring is set in white gold or platinum with a 3.5 carat Asscher-cut diamond.

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“[Pippa’s ring is] hugely practical because it’s quite flat and it will be very easy for her to wear,” jeweler Annoushka Ducas said in a previous interview. “It’s a very timeless piece that will look as good now as it will in 50 years time. It’s bezel fit making it a bit more modern, which fits in very well with her style. If [her fiancé] has chosen that on his own then he has done brilliantly!”

pippa middleton engagement ring getty images

Pippa and James with Pippa’s engagement ring (inset). (Photo Credit: Getty Images)

They’re moving pretty quickly.

Even though they’ve been friends for nearly a decade, James, 41, previously popped the question to Pippa in July 2016. The couple reportedly first began dating less than one year before their engagement following the author’s October 2015 split from longtime boyfriend Nico Jackson.

When and where is Pippa’s wedding?

This Saturday, Pippa and James will tie the knot at St Mark’s Church at around 11:30 a.m. in Berkshire, England. A reception for the couple is set to later take place at Pippa’s parents Carole and Michael Middleton’s Bucklebury, England mansion.

MORE: Prince Harry Has Gotten Approval From Queen Elizabeth to Propose to Girlfriend Meghan Markle!

Who is expected to attend?

Around 300 guests are expected to attend the lavish event, including Prince Harry’s girlfriend, actress Meghan Markle. Pippa’s royal niece and nephew, Princess Charlotte, 2, and Prince George, 3, will reportedly serve as a bridesmaid and page boy during the ceremony.

Though Kate will be in attendance at the wedding, she will not have a special role in Pippa’s bridal party as to “not upstage her sister.”

What kind of wedding dress will Pippa wear?

As for Pippa’s wedding dress? A royal style expert recently revealed the bride could wear something “lavish and romantic by Marchesa or upmarket luxe by Ralph & Russo.”

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“Other possibilities include Temperley, which both she and Kate wear regularly or Jenny Packham,” the style expert said, adding, “[Whatever the design], the dress will look as good from the back as the front!”

Her wedding cake will be locally made.

The couple ordered their cake from the London-based bakery Domino Purchas Contemporary Cakes, according to E! News. It cost them about $3,000 and it can feed more than 300 guests.

She’s worried about her soon-to-be brother-in-law!

James’ brother Spencer Matthews is known for playing a bad boy on reality TV — but Pippa has made it clear she doesn’t want any of his crazy antics to get in the way of her nuptials.

“She doesn’t want Spencer acting up during the day and has him warned to keep an eye on the booze,” an insider told E! News. “Strictly no pranks. He was planning to write ‘LAD’ on the bottom of James’ shoes!”

We can’t wait to see photos from Pippa’s big day!

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