What is the significance of Tita's being able to nurse Roberto? What is the significance of Rosaura's not having any milk?

This chapter further elucidates the theme of fictive and symbolic maternal figures in the novel. Because of Rosaura’s illness Tita assumes all maternal roles for the newborn Roberto. In a sense, she and Pedro achieve what they have always wanted, a family of their own.

Tita participates in a performance of motherhood that frequently characterizes those who behave as mothers without having any biological relation to the children they serve. However, Tita’s relation extends even further than a symbolic motherhood.