Sixpence, by Raymond Hopkins

Henry was born in prison, and brought up in a children’s home before going out to work, becoming a successful businessman. He leads a dull life since retiring until he meets Lynn, a young university student. On finding she is the granddaughter of his one and only love, Catriona, he offers her help towards her studies. During a study/holiday trip, matters between Henry and Lynn develop in ways neither had foreseen.