The Lonely Impulse by Merryn Ferguson

How random are acts of kindness? What memory triggers that generous action on the particular day? Three men, comrades in arms at the end of WW1, return to the Lowlands of Scotland, a farm in Cornwall and the East End of London to lives unrecognisable from those they had left, harbouring a secret that it is imperative that they conceal and which is only discovered in a diary entry one hundred years later. They were not to meet again. Over the years and spanning five generations one member of each family is prompted to an impulsive charitable act at a critical moment in their lives and the three families are eventually drawn together by one final act of kindness.