Answer:
What comes with your car, but travels more than your car?
I start in little but I end in full, you'll find me in half and complete.
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.
Tickle with your fingers and a song it will sing. Be careful, though, you may break a string. What is it?
What is filled with air and sometimes a gas, tied to a string and often seen on your birthday?
All about, but cannot be seen, Can be captured, cannot be held, No throat, but can be heard. Who am I?