What Am I Riddles

Question: I fasten to walk,
and unfasten to stop.

What am I?

Question: I give you a family of three:

One is sits down, and will never get up.
The second eats as much as is given to him, yet is always hungry.
The third goes away and will never return.

What are they?

Question: Give me food, and I will live. Give me water, and I will die. What am I?

Question: I am a child and a simpleton at once.
All are born with me,
But rarely am I possessed at death.

What am I?

Question: Of the king I am blue and of the peasant I am red.Of the frog I am cold and of the dog I am hot instead.What am I?