Creepy nursery rhymes

I've been reading nursery rhymes on and off for a total of four years now (little dude is four). And some of the nursery rhymes I've come across are just plain strange.

Rock-a-bye baby, on the treetop

When the wind blows, the cradle will rock,

When the bough breaks the cradle will fall,

And down will come baby, cradle and all

Why would anyone sing this to a baby?

And:

Three blind mice, three blind mice

See how they run, see how they run

They all run after the farmer's wife

Who cut off their tails with a carving knife

Did you ever see such a sight in your life?

As three blind mice...

While I was writing about this I decided to google for "creepy nursery rhymes". The information that came up was quite interesting. Go try. But take it with a pinch of salt. 

Oh oh oh... and as my kids listen to their songs I keep hearing this:

My body lies over the ocean

My body lies over the sea

My body lies over the ocean

Oh bring back my body to me...

Of course I know the right lyrics, but this is what I hear. All... the... time... 

Occupational hazard yeah?