There is no question that Calpurnia is, as Atticus later tells his sister Alexandra, an integral part of the Finch family. After the death of Jem and Scout's mother, Calpurnia comes to fill the role of housekeeper and babysitter for the children. Thus, she assumes the part of mother at many times. And, since she is treated as an equal part of the family by Atticus, Calpurnia feels comfortable with doling out instructions in manners to Scout. When Scout complains of Walter's having pour molasses all over his meat and vegetables, Calpurnia furiously calls Scout to the kitchen,
"There's some folks who don't eat like us,...but you ain't called on to contradict 'em at the table when they don't. That boy's yo' comp'ny and if he wants to eat up the table cloth you let him, you hear?"
When Scout counters that he is "just a Cunningham," Calpurnia cuts her off:
"Hush your mouth! Don't matter who they are, anybody sets foot in this house's yo' comp'ny, and don't you let me catch you remarkin' on their ways like you was so high and mighty!"
As punishment, she sends Scout back through the swinging door with "a stinging smack" so that she can finish her meal in the kitchen. When the children return from school later that day, however, Calpurnia has crackling bread, a favorite of Scout's, ready and tells the children that she has missed them--so like a mother. She even bends down and kisses Scout, much to Scout's wonderment. But, Calpurnia loves Jem and Scout as though they are her own children.