While there are rumors that Kate has been wearing a diamond on her left hand but not on her ring finer, there is also the possibility that Prince William will give his bride the sapphire and diamond engagement ring Prince Charles gave Lady Diana.
Prince William inherited the $1 million ring when his mother died and a source tells Star, " He wants her to wear it in honor of his mother."
Her wedding band will be made from gold, mined at the River Mawddach in North Wales.
And if Princess Diana's engagement ring is Kate's something blue, then her old may be the Spencer family tiara Lady Di wore on her wedding day. It was recently revealed that that the diamond encrusted tiara gave Diana a splitting headache.
The Budget and the Audience
Royal insiders are estimating that the royal wedding will cost $40 million (US) and the costs will be split between the state and the royal family.
Seven hundred fifty million people from around the world tuned into watch Prince Charles marry Lady Diana in 1981 and the estimated audience for their elder son's wedding is three billion viewers plus one million people are expected to line the bride's journey from Prince Charles' home, Clarence House, to St. Paul's Cathedral -- a journey she'll take in a glass carriage.
The Wedding Party
British wedding tradition is similar to American weddings in that the groom's brother, Prince Harry will stand as his best man and the bride's younger sister Pippa will be maid of honor.
With Harry's reputation as a partier, we're sure Prince William will have a wild bachelor party.
The Guest List
Royal families from around the world, heads of state (First Lady Michelle Obama and possibly President Obama will represent the United States) and celebrities are all expected to receive invitations.
After Sarah "Fergie" Ferguson's latest PR disaster - she was caught on tape selling access to Prince Andrew - she will probably not be welcome at the wedding.
And not just any celebrities will be invited. Only those who have been involved with William's Prince's Trust Charities should expect an invite and that list includes: Kelly Osbourne, Jay-Z and Beyoncé, Nicole Richie and Shania Twain. We should expect Princess Diana's dear friend Elton John as well as other rock legends - Paul McCartney, Phil Collins - at the ceremony too.
Star has a photo of Kate in a white V-neck wedding dress, by Australian wedding dress designer Collette Dinnigan, with a ruched bodice and a sash flowing from the waist but they can't confirm whether or not this is the dress. In an interview with Princess Diana's wedding dress designer David Emanuel, it is suggested that the dress Kate is wearing is too simple and the final design is probably more elaborate and may cost around $200,000.
With Westminster Abbey ruled out of the running because it was the location of Princess Diana's funeral, the magazine reports that Prince William and the future Princess Catherine, she prefers to be called by her legal name in public, will follow in his parents footsteps and say "I do" at St. Paul's Cathedral.
After the ceremony, a limited number of wedding guests will join the royal family at Buckingham Palace for a reception breakfast. The wedding menu is rumored to include salmon from Balmoral Castle in Scotland, lamb from the farm at Windsor Castle, fruit from the Queen's other homes and a variety of British delicacies. As aisledash.com reported via Twitter in April, the palace has already ordered dozens of crates of champagne to toast the happy couple.
Royal florist Rob Van Helden is booked to design the decor for the ceremony, reception and the bridal party's flowers. Kate's favorite white lilies will definitely be part of the decor along with hundreds of traditional English roses. Some of the flowers are expected to come from Prince Charles' garden at Highgrove.
James Middleton, Kate's younger brother, is a baker and owns The Cake Kit. It is assumed that he will design and create the royal couple's wedding cake. What it will look like is still unknown but the flavors will probably be a traditional British mix including raisins, currants and brandy.
More on Royal Weddings:
Learn more about Prince William, and his future princess, Kate Middleton
Browse our gallery of royal weddings from Queen Victoria to Prince William
In addition to charity work, Kate also has a full-time job. Find out what it is!
Swedish Crown Princess Victoria adds "sexist" wedding tradition to her June wedding ceremony
Photo Details: The commemorative plate featured above was designed by Woolworth's in 2006 in honor of a possible royal engagement. When an engagement was not announced the company decided not to manufacture the plate. Note the ? in the year.