The narrator, Scout, explains that Aunt Alexandra fits right in with the Maycomb ladies. She loves to gossip, and she has thoughts about all of the families. She says they have “streaks.” “Drinking streaks”, “gambling streaks”, “mean streaks”

From the text:

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.