The biggest similarity between these two novels is the theme of the conflict between the generations and the differences exhibited as parents and adults bring up children who come to be adults themselves. This is clearly persent in When I Whistle in the massive difference in outlook between Ozu and his son Eiichi, who seems incapable of treating any of his patients with any form of passion or concern. Eiichi is symptomatic of a new post-war generation who seems blind to the lessons that the older generation of Ozu and his contemporaries have had to face and learn, involving much suffering.
In Hard Times, the relationships between the generations is again a massive theme, as Thomas Gradgrind, having brought up his children to be profoundly disconnected from their emotions and imagination, has to face the consequences of his actions when he realises the massive mistake he has made and how both his daughter's unhappiness and sham of a marriage and his son's various problems and inability to function in society are largely down to his own educating of them to focus on facts alone. Here again, a father struggles to understand and to cope with his children.