Final answer:
The relationship between Mrs. Croft and her daughter Helen is not defined in the provided references. The excerpts show various literary characters and plots without specific details on Mrs. Croft and Helen.
Step-by-step explanation:
The relationship between Mrs. Croft and her daughter Helen is not explicitly detailed in the provided references, which discuss various literary characters and their interactions with others in their respective stories. The descriptions hint at themes of change, empathy, and longing in various relationships and scenarios from different literary works. Without specific information about Mrs. Croft and Helen, we cannot provide an accurate account of their relationship.