I have this in a book of Christmas music. It says the English text is by Richard D. Row and the music is by Mozart. There is no indication that Row's words are copyrighted. Which Mozart was the composer remains unclear. Anyway, here goes.

Sleep, Little Prince

Sleep my little prince sleep
the birds and the lambs watch will keep
silent each flower and tree
hushed is the hum of the bee
see the moon's silvery rays
fall where the rippling wave plays
in through the window they peep
sleep my little prince sleep

2. All in the manger is still
all on the meadow and hill
quiet is all in the house
stirring not even a mouse
day with its labor is o'er
darkness enfolds us once more
mother watch o'er thee will keep
sleep my little prince sleep.