The book, Churchill’s Little Redhead, tells the story of Celia Sandys who grew up with the man who famously led Britain through the Second World War.
The author and television presenter told the PA news agency: “He is a wonderful subject to write about. And I sort of was a bit nervous about writing about myself. Whether anyone would be interested to read it, well we shall see.
“I think it’s all me on the whole, it’s all my memories, and times that I had. I mean, it’s not all about my time with him. It’s about my life in general, which, you know, may seem very conceited that anyone would want to read about it, but I hope they will.”
The memoir, said to contain unique insights and revelations about the former leader, launched on Tuesday on what would have been his 147th birthday.
Sandys said: “People always want to ask what was it like having Winston Churchill as your grandfather. But he was the only grandfather I knew, so I thought every grandfather was just like that. He loved being with his family, that’s what he really liked.
“And when we were children, we spent a lot of our holidays with our grandparents. And so he would like to be sitting at the dining room table with as many of his family around as possible. We really enjoyed that and we would watch films after dinner.”
In the autobiography, Sandys described how she had received a toast from Churchill and then-US president Roosevelt following news of her birth on May 18 1943.
Sandys added: “I mean he was a very lovely family man. He liked going for nice walks in the country and I used to go with him when he was painting. I spent quite a lot of time with him in the south of France, because I used to go and stay with him.
“I was an available grandchild of an appropriate age and so I was lucky enough to be able to be available when the older ones were off doing other things and the younger ones were too young to spend a bit of time with him, so I was very lucky indeed.”