Transcript for Meghan Markle joins Prince Harry, Prince William and Princess Kate for charity event
our "Gma" cover story, the so-called royal fab four making their first public appearance of the year as we learn new details about Harry and Meghan's wedding. Eva pilgrim has the latest. Reporter: The fab four making their first official royal outing a joint appearance at the royal foundation forum. Catherine, Harry and I are collided to delighted to be here. Duchess indicate sharing her mission. All these underlying causes across so many different sectors and mental health just kept on coming up every time. Reporter: And Meghan Markle saying women need to use their voice. Women don't need to find a voice. They have a voice. They need to feel empowered to use it. Reporter: Prince Harry acknowledging they have a lot going on. We're pretty tied up with planning a wedding at the moment. Reporter: As we learn new details about the hottest wedding ticket of the year. Invitations for the wing are out. Mel B. Calling them proper, but not divulging any other details about the nuptials. Well, except -- Well, the spice girl, will they be performing at the reception? Reporter: The spice girls' rep bursting the bubble saying there is no plan for the group to perform. Prince Harry in this throwback picture from 1997 looks pretty smitten on the gal group. The spice girls are good friends with prince William and prince Harry from back in the day. Reporter: Speculation growing that Meghan has made one of the biggest decisions for her big day. Her wedding dress designer. Could longtime friend and London designer Rowland be on the short list? And prince Harry just said he's extremely excited and proud that my soon-to-be wife will join him in trying to make a difference. Girls around the world are going, ah. So exciting. Thank you. Thanks, Eva.
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