Answer:
Curtail me thrice I am a youth; behead me once a snake; complete I'm often used in truth when certain steps you'd take.
I come off of a beautiful creature which soars in the sky. I come off of a peckish creature which has a tail as mighty as the sun! I am sometimes dirty and parents beg you not to pick me up.
I am the word that has three syllables and twenty six letters.
I walk on 4 legs in the morning, 2 legs at noon, and 3 legs at night. What am I?
What is shaped like a box, has no feet, and runs up and down?
No matter how little or how much you use me, you change me every month.