What elements in the interpersonal dynamics of the Clutter family might account for Mrs. Clutter's illness?

We have good reason to believe that the health problems that Mrs. Clutter suffers from stem from her family relationships. It seems likely that Mrs. Clutter suffers from post-partum depression. We know this because the birth of her first baby first brought her these feelings, and because they have gotten worse with every subsequent child. Moreover, we also know that she feels overwhelmed by her household duties and wishes her daughter could take over. Therefore, her family relations and her role as a wife seem to account for much of her illness.