Transcript for New clues on who's designing Meghan Markle's wedding dress

Now we go to our "Gma" cover story. We are less than two weeks away from prince Harry and Meghan Markle's wedding and overnight new details about what the pride may be wearing down the aisle and, Amy, you put in a lot of research. I did, yeah, a lot of it and because billions of people, did you know that, a billion people expect to watch this wedding, so much anticipation for Meghan's dress, you may remember this now famous engagement photo of the happy couple. Well, this could be a clue. To Meghan's top secret wedding dress. Lin is laughing at me and who is designing it? Take a look. All eyes on Ralph & Russo, the designing couple who created Meghan's stunning engagement gown now slated to design the dress of the year. The wedding gown that will give meghankle a fairy tale ending as a real-life princess. Ralph & Russo have been working secret late nights at their London atelier on a hand skimped beaded bridal gown. Reporter: The tiara, among those most likely, the Spencer tiara Diana wore to her own wedding or perhaps a one-of-a-kind piece created from Diana's iconic collection like the emerald choker she made famous. There is the possibility she could choose the Spencer tiara and that Diana's family, the Spencer family would loan that to her for the wedding. Reporter: Meghan and Harry are putting the finishing touches on their big day. Meghan's closest friend and stylist Jessica Mulroney who helped Meghan picked the wedding dress actually flew into London recently to spend a weekend with Meghan and Harry going over final wedding plans and also attending a final dress fitting. Reporter: No maid of honor for Meghan. She doesn't want to pick between friends, William will reciprocate as best man. Charlotte and George will take a leading role and this photo taken by her mother cradling her brother Louis while wearing a sweater passed down by her big brother. Prince Louis will stay home. You don't have to miss a moment of the royal wedding because Michael is going to be live at Windsor next week. Hey. As we all count down to the wedding and robin will join him and then you and David Muir are anchoring live coverage of the five-hour event starting at 5:00 A.M. Eastern on Saturday, may 19th. Right here on ABC.

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