Answer:
I can travel from there to here by disappearing, and here to there by reappearing.
Today he is there to trip you up. And he will torture you tomorrow. Yet he is also there to ease the pain, when you are lost in grief and sorrow.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.
People are hired to get rid of me. I'm often hiding under your bed. In time I'll always return you see. Bite me and you're surely dead.
What kind of pet always stays on the floor?
What goes up the hill and down the hill, And spite of all, yet stand still?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?