Aesop's Fables, translated by Laura Gibbs (2002)

There was a woman who was the mother of two daughters, and she had married
them both off: one to a gardener and the other to a potter. She then paid
a visit to the daughter who was married to the gardener, and as they talked
about things in general the mother asked her daughter how she was faring.
The daughter said, 'In general, things are good, but please pray that
there will be some rainfall, so that the vegetables will be well-watered
and flourish accordingly.' The mother then left and went to see the daughter
who was living with the potter. She asked the daughter what she might
need, and the daughter replied, 'In general, things are good, mother,
but please pray that we have clear weather and hot sunny days without
a cloud in the sky so that the pots will dry out more quickly.' At this
point the mother said, 'But if you are hoping for clear skies and your
sister wants a downpour, then how am I going to pray for the two of you?'
The story shows that people who are conducting two opposite businesses
are bound to fail at both of them.

Note: Other versions of this story (included in Chambry's first edition
of the Greek fables) are about a father and his daughters.

Source:
Aesop's Fables. A new translation by Laura
Gibbs.
Oxford University Press (World's Classics): Oxford, 2002.
NOTE: New
cover, with new ISBN, published in 2008; contents of book unchanged.