Answer:
Old Mcdonald had this
What hatches without food?
What has one head, one foot, and four legs?
What gives life and love, and is there till they die? What can hide you and find you, heal you and feed you but should never give up on you?
It is in every mountain, it's not in any hill, it's not in all the world, and yet it's in the mill.
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?