Prince Harry Meghan Markle, Prince William and Kate's first joint engagement: All the photos

The fab four steps out in style!
Meghan Markle made her official debut in London alongside her family-to-be - fiancé Prince Harryand future in-laws the Duke and Duchess of Cambridge. It was their first time stepping out as a foursome for a public engagement, and Wednesday's (Feb. 28) outing couldn't have gone better. Laying out their vision for the future of their Royal Foundation, the American actress and the royals spoke passionately about the causes close to their hearts under the umbrella of the theme "Making a Difference Together" - from the Invictus Games, during which Meghan and Harry stepped out as a couple for the first time ever last year in Toronto, to the Head's Together campaign for mental health.
"We would not seek quick wins, but would strive to make a real and lasting difference," William said as he kicked off the event by explaining the Foundation's philosophy of making big changes over time. Click through for all of the best photos from the milestone outing...
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Both Meghan and her future sister-in-law looked beautiful in blue, with the former actress opting for a navy trench dress by Canadian-raised designer Jason Wu and the Duchess of Cambridge slipping into a cornflower blue number by maternity brand Seraphine.
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The bride-to-be made her intentions for her place in the Royal Foundation clear. Once she and Prince Harry marry on May 19, she will be its fourth patron, and revealed that she's ready to "hit the ground running" on women's rights.
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Meghan told the audience: "I hear a lot of people speaking about girls' empowerment and women's empowerment - you will hear people saying they are helping women find their voices. I fundamentally disagree with that because women don't need to find their voices, they need to be empowered to use them and people need to be urged to listen."
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Prince Harry, Meghan, Kate and Prince William haven't been photographed together since Christmas Day in 2017, when they joined other members of the Royal Family for the annual church service in Norfolk.
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Meghan also said the four of them brought their own perspectives to issues: "Thank goodness (there are) such differing personalities and everyone's very communicative because that's how you can really see bigger change - if everyone's thinking the same way how are you going to push the envelope, how are you really going to break through in a different sort of mindset?"
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Prince Harry joked about the tribulations of joining forces with family, saying, "working as family does have its challenges of course it does... the fact everyone is laughing means you know exactly (what I mean) - but we're stuck together for the rest of our lives."
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It seems that Meghan and Kate have developed a wonderful relationship and are clearly at ease with one another. The fab four shared a few jokes on stage and were in high spirits during the event.
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While royals generally steer clear of aligning with political campaigns, Meghan, 36, voiced her support for the #MeToo and #TimesUp movements. "Right now, with so many campaigns like MeToo and TimesUp, there's no better time to continue to shine a light on women feeling empowered and people supporting them."
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Harry and Meghan have previously spoken about how Prince William and Kate have warmly welcomed Meghan into the family. Chatting in their first televised interview as an engaged couple, Prince Harry said: "I'd been seeing her for a period of time when I literally didn't tell anybody at all. And then William was longing to meet her and so was Catherine. So, you know, being our neighbours we managed to get that in a couple of - well quite a few times now and Catherine has been absolutely… amazing as has William as well, you know, fantastic support."
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"You can't help but reflect on your own life and it's definitely had an impact on how sort of I look at how I mother, how we work as a family and you know, how we hope to bring up our children," Kate said as she revealed that her work with mental health and early intervention has taught her so much. William gave her the credit for launching Head's Together, saying, "Catherine was the one who joined the dots together for all of us. She was the one who came up with the idea and the concept as it were. Because Harry and I had never thought of doing a campaign as such before. When you tackle mental health, it was very difficult to know where to start. It's such a big issue and it's so entrenched in society in a negative way sadly, that we weren't quite sure how we would do it and how long it would take."
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BBC presenter Tina Daheley hosted the forum, asking the American actress about her thoughts on the foundation. Meghan responded: "To see the model of the foundation is really interesting because, while I've worked with larger NGOs, I've also worked with really small grassroots organizations where you can see a higher level of impact in my opinion, because there's a lot less red tape."
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"I think it's really good we've got four different personalities, we've all got that same passion to want to make a difference, but different opinions," Harry said of his excitement to have the foursome united for their individual causes. He is clearly thrilled for Meghan to come on board!
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In 2015, Prince Harry's fiancee showed her dedication to empowering the voices of women and their rights, working with the UN as a women's advocate. She received a standing ovation that year after making a powerful speech for UN secretary general Bahn-Ki Moon and more on International Women's Day
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