Answer: Angela Lansbury
The part of the reclusive Miss Eglantine Price is played by Angela Lansbury; this part was, incidentally, her first leading role in a musical film. The orphaned Rawlins children, evacuees from London to escape the Blitz, are Charlie, the eldest, played by Ian Weighill, middle child Carrie was played by Cindy O'Callaghan and Paul, the youngest of the three was played by Roy Snart.
Angela Lansbury was born in the Regent's Park area of London in 1925 and has enjoyed a long and varied career. Her life as an entertainer began in 1942 in Montreal, Canada where she worked as an act in a nightclub before earning a part in her first feature film 'Gaslight' in 1944. Lansbury is probably most famous for her role as Jessica Fletcher, a sort of American Miss Marple, in the popular and long running US television crime show 'Murder She Wrote'. Still active in 2015, Lansbury was created a Dame Commander of the Order of the British Empire for services to drama, philanthropy and charitable work in the 2014 New Year's Honours List by Her Majesty the Queen.