Explain "Aunt Alexandra fitted into the world of Maycomb like a hand in a glove, but never into the world of Jem and me."

Aunt Alexandra comes to spend some time with Jem and
Scout. The trial is going to start soon, and Atticus wants Aunt Alexandra's help with
the kids. Jem and Scout are less than happy to learn that Aunt Alexandra is coming to
stay with them. Aunt Alexandra is from the old school of the South, where people
believed that a person's social standing was based upon how "good" their families were.
This is in direct opposition to what Jem and Scout
believe.

"Aunt
Alexandra fitted into the world of Maycomb like a hand into a glove, but never into the
world of Jem and me. I so often wondered how she could be Atticus's and Uncle Jack's
sister that I revived half-remembered tales of changelings and mandrake roots that Jem
had spun long ago."

Atticus
has taught Jem and Scout to judge a person on the way they treat other people, and that
a good family does not make a person good or bad. It is the person's character that
makes them a good person. Aunt Alexandra is very caught up in the society thing. She
believes that a family of good standing is what matters, and nothing else. Atticus, Jem
and Scout know better.