The neckline on her recent outfit is very similar to Meghan's style.
The couple were invited to contribute to a painting, leaving them in stitches.
William and Middleton have been vocal about their advocacy for mental health, starting their Heads Together campaign, along with Prince Harry, and aiming to combat the stigma surrounding mental health.
Kate and William also met with Dairo Vargas, a contemporary fine artist from Columbia, who is creating an original piece of art at the summit, inspired by the day's events. He added: "She was genuinely knowledgeable and excited about photography - particularly the history".
This saw the couple break out into laughter along with the crowd.
You can see more on that here and while Kate was at the exhibition, she had a chat with Martin Barnes who is one of the senior curators of photography at the much-esteemed museum. The initiative was started by Dixon Chibanda and teaches the women to become lay health workers.
Liverpool and United in transfer fight for Ramsey
Manchester City, Liverpool and Chelsea are all on 20 points after eight games played, with Arsenal on 18 in fourth place. It only took Ramsey a matter of seconds to put Arsenal 3-1 up with a sweet finish courtesy of an Aubameyang's assist.
The duchess first showed off the Emilia Wickstead dress on a trip to Germany past year.
She has expressed her love for photography and has taken portraits of her children Prince George and Princess Charlotte in the past.
Last month Prince William opened up about the emotional toll of witnessing suffering during his time as an air ambulance pilot.
Erdem is a much beloved designer of the royals, with speculation around whether the brand has designed Princess Eugenie's wedding dress for her nuptials on Friday.