Kate accompanied her husband William and the Duke and Duchess of Sussex outside Windsor Castle yesterday where they met with members of the public.
Banita Ranow, 28, who was among those waiting to see the Royals, said Kate revealed the first words the four-year-old Prince said after being told the sad news.
She told the PA news agency: “Louis said ‘at least Grannie is with Great Grandpa now’.”
Another onlooker said it was ‘fabulous’ to see the siblings and their partners reunited, despite the sad circumstances.
She said: “I felt so emotional and I felt the Queen would have loved it. I just hope in the future they remain like that and that the brothers come together, and the families.”
William shared a touching tribute to his late grandmother at the weekend, saying his children had created memories ‘that will last their whole lives’ with the Queen.
The statement read: "On Thursday, the world lost an extraordinary leader, whose commitment to the country, the realms and the Commonwealth was absolute. So much will be said in the days ahead about the meaning of her historic reign.
“I, however, have lost a grandmother. And while I will grieve her loss, I also feel incredibly grateful. I have had the benefit of The Queen’s wisdom and reassurance into my fifth decade.
“My wife has had twenty years of her guidance and support. My three children have got to spend holidays with her and create memories that will last their whole lives.
"She was by my side at my happiest moments. And she was by my side during the saddest days of my life. I knew this day would come, but it will be some time before the reality of life without Grannie will truly feel real.
“I thank her for the kindness she showed my family and me. And I thank her on behalf of my generation for providing an example of service and dignity in public life that was from a different age, but always relevant to us all.
“My grandmother famously said that grief was the price we pay for love. All of the sadness we will feel in the coming weeks will be testament to the love we felt for our extraordinary Queen.
“I will honour her memory by supporting my father, The King, in every way I can.”
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