Answer:
Kills the bad ones and the sad ones. Tightens to fit, so one size fits.
I don't think or eat or slumber. Or move around or fear thunder. Just like you I look the same but I can't harm you or be your bane.
White fat and fluffy, May even look like a puppy. Seems heavy but is light, Floats about without a worry, But if it turns dark you have to hurry!
When young, I am sweet in the sun. When middle-aged, I make you gay. When old, I am valued more than ever.
Man walks over, and man swims under. In times of war, it can be burned asunder. What is it?
What is so fragile that saying its name breaks it?
Difficult
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?