It was because Elizabeth “was extremely immature, like a child still, attracted to dolls, to old slippers; a perfect baby; ……. ” (Woolf, p. 127)

Back then in that era, adult young women were not commonly seen to be still liking dolls, or attached to old personal possessions.

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This is the main book review https://booksreviewsandmore.com/why-does-peter-walsh-have-an-axe-to-grind-with-clarissa-dalloway/