Narcoleptics spontaneously fall asleep, often
at inopportune moments — even while
laughing at a joke, or in the middle of an angry outburst.
Maybe if you're a native speaker, you're not aware of all the echoes of the words that share a common root, but you know, it really struck me that [Arabic has] a word for «child» that relates to things like «dawn» and «soft clay» but also «one that arrives
at an
inopportune moment,»» she
laughed.