Hi Mosh,
Now just for your interest and to help you confirm or otherwise that this is your Keith, here are the possible births of the parents from freebmd .
Chisnall, Edna. Mother Topping. June 1/4 1921. vol 8c pg 336 Warrington
Turton, Jack Mother Burgess Sept 1/4 1920. vol 8c, pg 309. Warrington.
Now, I am not good at the Counties, but is Warrington close to Nottinghamshire where you knew Keith?
ADDING: There is a birth for a Ronald Turton in Nottingham in 1918
Turton, Ronald. Mother Chambers. June 1/4 1918. Nottingham. 7b pg 501
And this is the best I can see for Cynthia
WildE Cynthia. Mother WildE Sept 1/4 1920 New Forest. 2b, 1438
It may sit with cando's 1961 finding.
Sue