Telling the Sunday Times about their bond, Sophie said: “I guess not everyone’s grandparents live in a castle, but where you are going is not the important part, or who they are.
“When they are with the Queen, she is their grandmother.
The Countess of Wessex has also previously shared the sweet moment Louise realised who her gran was, telling the BBC: “It happened a little while ago. It was much more of a shock to the system.
“It was only when she was coming home from school and saying, ‘Mummy, people keep on telling me that grandma is the queen,’ and I asked her, ‘Yes, how does that make you feel?’ And she said, ‘I don’t understand.'”
Sophie added: “I don’t think she has grasped that perhaps there was only one queen.”