Minor Character Change

A minor character in the book The Husbands Secret  is John-Pauls mother. She is a very minor character because she is very briefly introduced in the story and doesnt play a major role. She comes over to Cecilia's home (John- Pauls Husband) every week to have tea and a fresh baked pastery. This plays a very small part in the plot of the story. John Pauls mother knows about how her son murdered Janie. This could be a signifigant part in the story but the author writes it to be insignifigant to the story. If the author were to make this charcter a more singifigant character in the book she would have to change some things in the plot. For example Cecilia would tell her husband that his mom knew about the girl that he murdered. This would change the way that John-Paul goes about his daily life now knowing he and his wife are not the only people who know of what he did. I think that this change would improve the plot of the story in a major way. For example Cecilia and John-Pauls mom could team up on him and turn him in to finally  give him the punishment that he deserves. I personally think that John-Paul should be punished for what he did. If you were Cecilia would you turn your husband in for murder?