As I understand it. Night terrors originate during stage 4 non-REM
sleep. They are assocaited with non-REM dreams. Klonopin and the
benzodiazepines in general, reduce anxiety, reduce stage 4 sleep, and
are anticonvulsant. Stage 4 sleep shows highly synchronous low
frequency EEG patterns. which look to me a lot like some forms of
seizure to me. Put these facts together anyway you like.