Answer:
I am a precious stone as clear as diamond. Seek me out while the sun's near the horizon. Though you can walk on water with my power try to keep me and I'll vanish in an hour.
My first is in riddle but not in little. My second is in think but not in brink. My third is in thyme but not in time. My fourth is in mother but not in brother. My last is in time but no t in climb.
What loses its head in the morning but gets it back at night?
I am a busy worker who is a water mammal.
I am higher than the king. What am I ?
I am your mother's brother's only brother in law. Who am I?