How does the author use foreshadowing in Betsey Brown?

In Chapter Twelve, the brief discussion of Carrie's previous mistakes, ones that have caused her to leave her home and lose connection with her children, foreshadow some dark calamity around the corner. While the children clearly love and believe in her, Carrie has a realistic view of her own limitations, and still "prays to a benevolent God that she's reformed and moved onto a better way."