I must confess I'm the one who introduced the song

But this is what my youngest requests I sing to him every night before he goes to sleep:

She sailed away
on a bright and sunny day
on the back of a crocodile.

"You see," said she,
"he's as tame as he can be.
I'll ride him down the Nile."

The croc winked his eye
as the lady waved goodbye
wearing a happy smile.

At the end of the ride,
the lady was inside
and the smile was on the crocodile!

When I finish, he asks the same question -- "Why is the smile on the crocodile?"

"Why do you think?" I ask.

"Because the crocodile ate the lady," he shouts with glee, "and she's DEAD!"

Ahh, such sweet innocence.