Answer:
What is weightless but it needs two person to hold it?
I am mother and father, but never birth or nurse. I'm rarely still, but I never wander.
It has no top or bottom, but it can hold flesh, bones, and blood all at the same time.
In your fire you hear me scream, creaking and whining, yet I am dead before you lay me in your hearth.
My life can be measured in hours, I serve by being devoured. Thin, I am quick. Fat, I am slow. Wind is my foe.
When is it bad luck to see a black cat?