what is the smilie that aunt baba used to express how Nai Nai's life had ended? Explain what it means. describe its effect on the reader?

I believe the simile is, “Nai Nai’s life had evaporated like an episode in a spring dream.” This means that her life vanished/evaporated so quickly.

I believe the similie "Nai Nai's life had evaporated like an episode in a spring dream." means:

Nai Nai died unexpectedly and very quickly.