Answer:
By Moon or by Sun, I shall be found. Yet I am undone, if there's no light around.
The itsy bitsy teeny weeny yellow polka dot variety is quite popular.
Three little letters, a paradox to some. The worse that it is, the better it becomes.
It stands upright and can be quite grand. Its secret is not hidden but right at hand. What is it?
My first master has four legs, my second master has two. My first I serve in life, my second I serve in death. Tough I am, yet soft beside. Against ladies cheeks I often reside.
I am your mother's brother's only brother in law. Who am I?