Tracing my mum's early childhood

I am trying to trace my mum’s early childhood years. I believe up to the age of 14 she lived initially around Thundersley and then Hadleigh, eventually moving to Southend after finishing school. I remember her mentioning that she attended Hadleigh School. She was born in 1932 and I think moved from Thundersley to Hadleigh in 1939 (possibly living at the Salvation Army residence Castle House where she went to Hadleigh School).

My mum’s name is Phyllis Flicker and was born in 1932. Her mum’s name was Florence  Flicker. My mum may have been looked after by friends of my grandma for a while and there is a hint that the friends surname may have been ‘Pettitt’.

Any information such as school photos or school registers to check her name or face against would be gratefully received. The schools that would be of interest between 1937 and 1946 are Thundersley School, Hadleigh School and Westleigh School.  I enclose a picture of my mum who is the little girl with the lighter coloured hair on the left next to the elderly lady and black dog. Possibly, the lady behind my mum is Mrs Pettitt.