Ms Hicks told the Daily Mail: “It was when my mother was describing the Coronation.
“There were these extraordinary scenes of history unfolding and all the pageantry around but my mother was focused on this very young woman, completely alone, with that extraordinary light shining on her.
The Queen would later ask her close friend to give her a detailed description of the events of that terrible day.
In the documentary, Lady Pamela revealed: “She asked me to tell her exactly what had happened because she adored my father.
“And then, silence. The Queen’s emotions are all inside, always. She is very strong.”