Lady Eliza Spencer - the niece of the late Princess Diana - has heaped praise on her aunt, recalling her "warm, maternal and loving" personality.
The 28-year-old twin - who spent her early years at Althorp, Diana's family home and final resting place, before relocating to South Africa - said: "We always just knew her as our aunt.
"Growing up in South Africa, I really had very little idea of how significant she was in the world until I was much older."
Eliza thinks the Princess - who died in August 1997, aged 36 - created a real connection with children.
She revealed to Tatler magazine Diana's hidden talent: "She always made an effort to connect with us as children and had a talent for reading children's hearts."
Eliza - whose father is Earl Spencer, Diana's brother - admitted she didn't grasp the scale of the Princess' fame during her younger years.
She confessed: "As a child, I realised the enormity of the loss for my father and family.
"It was only later that I came to understand the significance of the loss of her as a figure in the world."
Prince William previously admitted to being "in a state of shock for many years" after Diana's death.
Asked if he grieved her death, the 38-year-old royal replied: "Probably not properly. I was in a state of shock for many years."
Asked if he literally meant that it took "years" to come to terms with Diana's death, Prince William added: "Yes, absolutely.
"People might find that weird, or think of shock as something that is there, it hits you, then in an hour or two, maybe a day or two, you are over it.
"Not when it is this big a deal; when you lose something so significant in your life, so central, I think the shock lasts for many years."