Just because I didn't hear it with the n-word in the 50's, in my own home, doesn't mean it wasn't being sung next door that way. When I found out about it later, it turned out that all my friends had heard it the other way. So there ya go. I was "lucky," I got to miss ONE of many cultural messages.
The point was, we all got them, one way or another. Even if we did not realize that's what they were at the time, or what they meant. They all glom up together in our unconscious. So I don't sing this one to babies now. The fun of it went out of it, for me, retroactively.
Hey, I think I'll change my name to YMMV.