Obviously Zepplin ignorant here, what happens if you listen to it backwards? I have heard it a few times, I thought it was about the lead singers child who died or something like that. I could be getting it confused (I am good at that) with another song.Stair way to heaven

hello
Does anybody really belive that listening to "stair way to heaven" (Led Zeppelin) is bad in any way......? as long as you don't listen to it backwards?
Thanks