Enjoy ALL of life, even the unexpected torrential rain and subsequent mud puddles. There is always something to be gained from what may first seem like an unpleasant experience.
Hmmm... Or was it:
Live in the moment and enjoy life's windfalls in whatever form they take. Fully embrace life's random opportunities to experience joy.
Or maybe it was:
Bathe while you can, where you can ... for you never know when it will rain again.
Actually, now I am thinking that it was more like this:
Ducks liketh the water, always.