Answer:
In the night a mountain, in the morning a meadow.
I go around in circles, but always straight ahead. Never complain, no matter where I am led.
In buckles or lace, they help set the pace. The farther you go, the thinner they grow.
Glittering points that downward thrust. Sparkling spears that never rust.
What has six faces, But does not wear makeup. It also has twenty-one eyes, But cannot see?
I am your mother's brother's only brother in law. Who am I?