Answer:
What stays the same size no matter how much they weight?
I am free for the taking. Through all of your life, though given but once at birth. I am less than nothing in weight, but will fell the strongest of you if held.
Plant whose name sounds like a dish full of dairy spread.
My first is in fish but no in snail. My second is in rabbit but no in tail. My third is in up but not in down. My fourth is in tiara but not in crown. My fifth is in tree you plainly see. My whole a food for you and me.
It is worldwide, but once only a spider could weave one
I am owned by Old McDonald.
Difficult
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?