Sydney's father was John Cort Procter (1860-1932), corn merchant, of Liverpool. Sydney's mother was Helen Imrie (1866-1940), a minister's daughter from Scotland; her mother had been Mary Morrison, hence Sydney's middle name. Sydney never married.
Sydney's elder brother Ian (1902-78) was also a schoolmaster, and is believed to have taught for some time at Kingsmead, Hoylake. The names of two of their cousins could be seen on an Honours Board at Kingsmead.
Sydney went to Birkenhead School, then studied at Liverpool University; class-lists show that his BA was conferred on 9 July 1927 - he had gained Class II-II honours in the School of History (Medieval and Modern).
After his graduation, Sydney started teaching at The Leas; he was musical, and played the harmonium for daily services, which took place in the dining hall before the fitting-out of the Chapel in 1949. Sydney seems to have been well-enough liked as a master, going by the rather unimaginative nickname Proggy. For some years he was a director of The Leas (Hoylake) Ltd, alongside the headmasters Francis Fetherstonhaugh and Henry Silcock.
In 1957 the headmasters required him to resign his directorship and to leave the school.