This is a poem from Kenn Nesbitt. Here's how it goes:
I've got a secret!
Oh, I've got a secret!
But I made a promise I wouldn't repeat it.
I've got a secret!
Yes, I've got a secret!
But I took an oath and I vowed I would keep it.
Nothing and no one can make me reveal
This wonderful secret I swore I'd conceal.
No form of torture can make me disclose,
This secret I promised I wouldn't expose
From now until doomsday my secret I'll keep,
I won't breathe a whisper or utter a peep.
Unless you assure me that you'll keep it too,
Then maybe, just maybe, I'll share it with you.