Answer:
Proof you've done your time in school
A gentleman whose offspring have successfully produced offspring of their own.
They come to witness the night without being called, a sailor's guide and a poet's tears. They are lost to the sight each day without the hand of a thief.
It keeps you on the ground and stops things from floating around. What is it?
What was the first man made invention that could see through a wall?
A little house full of meat, no door to go in and eat.