Whilst children sleep.......for seth

[serge gurkski]

Well, the way I understand those 2 lines is that darkness lurks in the corner, waiting. When shadows come to end the day, darkness takes the chance to enter people's dreams. I don't know, the way those lines are phrased just doesn't sit well with me.

I know what you are saying. Maybe your analysis is too deep. I read it more as a lullaby. And: that is does not sit well with you (and with any reader /listener) might even be the intended effect.
I simply like the word play. ,-)