I roar, I rumble, I burble. I splash, I murmur, I gurgle. I can sound like thunder. I can pull you down under.

A big purple goodness, given many names, one of them would be a chickens kids with some fauna

I start out small, yet grow to be, a winding path that feeds the sea.

I run long and thin but within the walls, I thrive and scale without falls.

You're going to want this for my first four. My last three shares the same end as a turtle.