What is Aunt Alexandra's reaction to Atticus's defeat in Chapter 22 of To Kill a Mockingbird?In chapter 22, when Atticus comes home from the trial,...

As Atticus and the children return home in Chapter 22, Aunt Alexandra is waiting up, and, although she is in her dressing gown, Scout notes that she appears to be yet wearing her corset.  This particular detail indicates that Aunt Alexandra does not wish to be relaxed, for she feels that she must maintain her composure and strength for Atticus's arrival.

'I'm sorry, brother,' she murmured.  Having never heard her call Atticus 'brother,' I stole a look at Jem...

In this remark, Aunt Alexander demonstrates a familial loyalty to Atticus.  This emotion is certainly not out of character inlight of her previous discussions about the Finch family tree.  For, family loyalties supercede other feelings. Continuing in her solicitous manner, Aunt Alexandra responds to Atticus's comment about the prejudice of the jury being just as much a part of Maycomb County as the missionary teas:

'You are the last person I thought would turn bitter over this.'

Clearly, the sister loves her brother and is concerned about the emotional effect of the Tom Robinson trial upon her brother Atticus.