Hi,there.
I remember the following was being discussed in a certain post here:
In the Japanese original version, does Klaus actually sing himself to sleep with "Mary Had A Little Lamb" or does he sing another close nursery rhyme?
Unfortunately I could not find the post though, I had wanted to find a song video of Japanese version of "Mary Had a Little Lamb", which offers Japanese lyrics Klaus actually sings to himself in canon and I did (^ _^) :
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