Hush little baby don't say a word mummy's gonna buy you a mocking bird
and if that mocking bird don't sing mummy's going to buy a diamond ring
If that diamond ring is brass mummy's going to buy you a looking glass
and if that looking glass gets broke mummy's going to buy you a billy goat.
If that billy goat falls down you needn't worry
'cause you're still the sweetest little Girl/boy in town.

I have been singing this version to my kids/grandchildren for some 30 years now and I got it out of a nursery rhyme book.