Answer:
What is as big as you are and yet does not weight anything?
Die without me, never thank me. Walk right through me, never feel me. Always watching, never speaking. Always lurking, never seen.
I turn around once. What is out will not get in. I turn around again. What is in will not get out.
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard.
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.
I am your mother's brother's only brother in law. Who am I?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?