I think you should probably go with Miss. Maudie or Calpurnia. I'll go with Calpurnia. Calpurnia is the black cook and cleaner for the Finch family. Calpurnia is very much a mother figure to Scout. We see this early in the novel. She does not coddle Scout; instead she comes off as a harsh disciplinarian, “Our battles were epic and one-sided. Calpurnia always won, mainly because Atticus always took her side. She had been with us ever since Jem was born, and I had felt her tyrannical presence as long as I could remember." Still, implicit in Calpurnia's admonishments of Scout, there is always a sense that she cares. Her discipline is always tempered with deep concern for Scout's well-being. It is always just below the surface. A great example is when Scout is inadvertently rude to the Cunningham boy at dinner. Calpurnia takes Scout to the kitchen,
"That boy is your company. And if he wants to eat up that tablecloth, you let him, you hear? And if you can't act fit to eat like folks, you can just set here and eat in the kitchen." Calpurnia speaks like a parent and indeed she is. As Scout matures and her world begins to rapidly change Calpurnia seems to know and again is there for Scout, "Calpurnia bent down and kissed me....." By the end of the novel Scout comes to know that Calpurnia is a special woman. Not only does she bridge the gap between the black and white communities, she (more importantly) instils her values and ethics on Scout. Calpurnia is the mother figure that helps make Scout into the wonderful character that she is.