Why does Alexandra think Atticus should dismiss Calpurnia, and how does Atticus respond to the suggestion in To Kill a Mockingbird?
Alexandra primarily believes that since she has decided to come and live with Atticus and his family, Calpurnia is no longer essential to the household. Alexandra will provide the motherly touch that Jem and Scout need, she believes, eliminating this aspect of Calpurnia's responsibilities. Since Alexandra is a great cook, she will also replace Calpurnia in this regard. Alexandra also believes that Calpurnia has not done a sufficient job in turning Scout into a lady, and she tells Atticus that
"... it's all right to be soft-hearted, you're an easy man, but you have a daughter to think of. A daughter who's growing up.
"... We don't need her now."
Atticus will hear none of it, however. He believes Calpurnia has done a great job of bringing up his children. Besides, Atticus considers Cal "a member of this family."
"... Calpurnia's not leaving this house until she wants to. You may think otherwise, but I couldn't have got along without her all these years... Besides, sister, I don't want you working your head off... We still need Cal as much as we ever did.
"Besides, I don't think the children've suffered one bit from her having brought them up. If anything, she's been harder on them in some ways than a mother would have been... she's never let them get away with anything...and another thing, the children love her."
The subtext behind the reason that Aunt Alexandra thinks Atticus should dismiss Calpurnia is that Scout is becoming too friendly with African-American people and wants to visit Calpurnia at her house. While Aunt Alexandra says that Scout is too old for Calpurnia, Alexandra's real reason for wanting to get rid of Calpurnia is that Alexandra thinks Scout is too close to African-Americans through Calpurnia. However, Atticus immediately rejects this idea and says that Calpurnia is "a faithful member of this family" and will leave her position only when she wants to. He also says that Calpurnia has been harder on Jem and Scout than a real mother would have been and that Calpurnia has not been indulgent towards the children. Atticus feels that Calpurnia has a good sense of how to bring up children and that Jem and Scout love her.