Answer:
What is given but kept by the giver?
You saw me where I never was and where I could not be. And yet within that very place, my face you often see.
It is a sound of empty, speak and it'll talk back plenty. But all the more you yack, you'll get the same words back.
Though blind as well, can lead the blind well.
The eight of us move forth and back. To protect our king from the foes attack.
I am your mother's brother's only brother in law. Who am I?