what "subtle change" does scout notice in her father?

By chapter 16 Scout has begun to notice all the pressure on her father. The weight of their world is upon him and he works harder than ever. Atticus used to be home more but now Calpurnia and Aunt Alexandra must take over much of the care. Although Atticus won't admit it openly, he thinks that they have a chance at the Tom Robinson trial even though he has been disappointed in his town as of late.