Screaming youngsters can have some lungs on them.
And yes, I may be at an event where there’s a kid having an unholy tantrum and screeching as well as any black metal vocalist
So technically not a shower thought, but I will be having that thought the next time I’m listening to black metal in the shower.
If I remember correctly, Steve Vai had a recording of his wife in labor in one of the tracks from “Sex & Religion”. Devin Townsend, who was his (fairly young) vocalist then, was quite disturbed by it.
This is more “white metal” than black metal though.