Answer:
Brothers and sisters I have none but this man's father is my father's son. Who is the man?
What goes up when rain comes down?
What is so delicate that saying its name breaks it?
It comes only before, it comes only after. Rises only in darkness, but rises only in light. It is always the same, but is yet always different.
Other terms for this handy device include doohicky, doo-dad, and whatchyamacallit.
Be sure to shout for its answers are weak, but there is no language it cannot speak.