Answer:
With a halo of water and a tongue of wood, stone as skin long I stood. What am I?
I am often sold by children entrepreneurs in summer time
Drop me and the world will shatter. You can always find me where you empty your bladder.
When set loose I fly away. Never so cursed as when I go astray.
To cross the water I'm the way. For water I'm above I touch it not and truth to say I neither swim nor move.
I am your mother's brother's only brother in law. Who am I?