[1] Miller's first film appearance was at the age of six, when she played Gladdie, a little girl who helps Sidney Stratton escape from an angry mob in The Man in the White Suit.
"[2]: 220 The following year, a casting agent at Ealing invited her to do a screen test for the title role in Mandy, which was also directed by Mackendrick.
Referring to the test, Mackendrick later said, Mandy's performance was so astonishing that the unit was struck rigid, holding its breath, with this electrifying silence on the floor.
[2]: 221 Her role in Mandy was that of a deaf-mute child whose parents (played by Terence Morgan and Phyllis Calvert) did not know how to cope with bringing her up.
Miller made two popular single records: "Snowflakes" and "Nellie the Elephant", the latter produced by George Martin.