Pretty John Watts is asked to drive out the rats, but the rhyme changes its mind and lets the house mice stay to nibble away. A forgiving little song about pests.
From Mother Goose / Nursery Rhymes (traditional). See the whole collection.
Pretty John Watts,
We are troubled with rats.
Will you drive them out of the house?
We have mice, too, in plenty,
That feast in the pantry,
But let them stay
And nibble away,
What harm in a little brown mouse?
Public domain. Text from The Real Mother Goose (Blanche Fisher Wright, 1916), via Project Gutenberg. View the source edition