My uncle has sent me a little more information about my grandfather's story. Alas, it does not have a happy ending.
By 1941 my grandparents had five children and grandad was still working at the docks, which was classed as vital work. However, he left his job and joined the army, the Royal Engineers, and saw quite a lot of action during the war. I am told he was involved in the hazardous task of mine clearing in North Africa which could not have been easy on the nerves.
On his return home after the war ended he was very ill and was admitted to hospital for a time. As well as his physical problems he was also suffering from what would now be called Post Traumatic Stress Disorder, which was not recognised back then.
He never really managed to fit back into civilian life and died in his fifties after suffering from Parkinson's disease during his final years.
I have vague memories of him from my early childhood but these are mainly of a shrunken man with severe tremors, unable to speak coherently and sitting in a wheelchair.
I am sad to realise that he suffered so, and that I never got to know him properly.