Answer:
Two in a whole and four in a pair. Six in a trio you see. Eight's a quartet but what you must get is the name that fits just one of me.
I am a mother from a family of eight. Spins around all day despite my weight. Had a ninth sibling before founding out it's fake.
I am an instrument capable of making numerous sounds but cannot be touched or seen. What am I?
You use me between your head and your toes the more I work the thinner I grow.
I go up and never come down no matter how hard you wish. As I get higher, more wrinkles crawl on to the face. What am I?
I am your mother's brother's only brother in law. Who am I?