Prince Andrew put his arm around his youngest daughter as she wiped away tears during an emotional outing to see floral tributes left to the Queen.
Members of the royal family attended a short church service near their Balmoral estate before carrying out a short walkabout.
The grieving family looked very emotional as they read cards and messages left for the Monarch, who passed away at the castle earlier this week.
Dressed all in black and standing next to her older sister Princess Beatrice, Eugenie was seen wiping tears from her eyes as her dad comforted her.
Asked by a mourner how things were, Andrew said: “We’ve been allowed one day, now we start the process of handing her on.”
He added: “It’s nice to see you, thank you for coming.”
The Yorks were joined by Princess Anne, Zara Tindall, Peter Phillips, Prince Edward, Sophie Wessex and Lady Louise Windsor.
Zara was also seen looking emotional during the short visit, while Sophie clutched her daughter's hand as they walked through the street.
Well-wishers who had gathered to see the royals broke out into a round of applause before the royal family walked towards the castle gates to go back inside.
Prince Edward thanks people for travelling to the royal estate, telling a group from Glasgow: "Thank you very much for coming all that way, we appreciate it."
Following doctors' concerns about the Queen's health earlier this week, members of the royal family rushed to Balmoral to be the Queen. However she sadly passed away before they arrived. Charles, William and Camilla returned to London while Harry went back to Windsor, where it's believed Meghan is staying.
Other royals have since made the journey to the Scottish estate, which Princess Eugenie once described as the place where the Queen was at her happiest.
Speaking on ITV's documentary Our Queen at 90, Eugenie, reminisced over family holidays at Balmoral.
She said: "It's the most beautiful place on earth. I think Granny is the most happy there, I think she really, really loves the Highlands…walks, picnics, dogs, a lot of dogs, there's always dogs, and people coming in and out all the time.
"Family-wise we're all there, so it's a lovely base for Granny and Grandpa to be - for us to come and see them up there where you just have room to breathe and run."
The walkabout comes hours after King Charles was officially appointed Head of State in a meeting of the Accession Council this morning.
He was joined by Camilla and Prince William for the historical event, which was televised for the first time in history.
Charles signed the declaration using a fountain pen, with ink from a silver pot that was gifted to him by sons William and Harry.
Last night he gave his first public address since becoming Monarch, paying tribute to the Queen and pledging a life of service to the Crown.
He said: "I speak to you today with feelings of profound sorrow. Throughout her life, Her Majesty The Queen – my beloved Mother – was an inspiration and example to me and to all my family, and we owe her the most heartfelt debt any family can owe to their mother; for her love, affection, guidance, understanding and example.
"Queen Elizabeth was a life well lived; a promise with destiny kept and she is mourned most deeply in her passing. That promise of lifelong service I renew to you all today. "
He also used the speech to announce that Prince William and Kate will become the Prince and Princess of Wales. He said: "As my Heir, William now assumes the Scottish titles which have meant so much to me
"He succeeds me as Duke of Cornwall and takes on the responsibilities for the Duchy of Cornwall which I have undertaken for more than five decades. Today, I am proud to create him Prince of Wales, Tywysog Cymru, the country whose title I have been so greatly privileged to bear during so much of my life and duty.
"With Catherine beside him, our new Prince and Princess of Wales will, I know, continue to inspire and lead our national conversations, helping to bring the marginal to the centre ground where vital help can be given."
There was also a nod to Prince Harry and Meghan Markle, adding: "I want also to express my love for Harry and Meghan as they continue to build their lives overseas."
