Once upon a time,an old lady had two sons.
the elder was selling umbrellas
the yonger was selling salt
the old lady worried about the two almost everyday.
about what?
once the sun came out,she would say," umbrellas won't sell well in sunny days!" she was worrying for the elder.
once it rained,she would murmured," what to do with the salt in such rainning days!" thus,she was worrying for the yonger.
the old lady kept worrying and worrying until one day,she got sick.
the two sons didn't know what to do.
fortunately,a wisdom came up with an idea,"sunny days are for drying the salt,so just be happy for your younger son; rainy days are for selling umbrellas,and you should be happy for your elder son.thus,nothing else is worth worrying about!"
as expected,the old lady suddenly undersood.and she got happy and healthy ever after.