Answer:
I am partially baked. I am not completely lit. I am a portion of the moon. I am lesser than full wit. I am a divider of the hour. I am not a total lie. I am a sibling through one parent.
It's been around for millions of years, but it's no more than a month old. What is it?
What devours all and can kill a king. Destroy a town and crushes mountains down?
When is 1500 plus 20 and 1600 minus 40 the same thing?
What has no hands but might knock on your door, and if it does you better open up?
What never gets any wetter no matter how hard it rains?