I can't find the "stone beast".

Hint 1 of 5:

It is not a beast made of stone.

Hint 2 of 5:

It is a stone with a beast engraved on it.

Hint 3 of 5:

The old woman says "wash the feathered killers" there.

Hint 4 of 5:

There is obviously water nearby.

Hint 5 of 5:

The ford (small crossing) nearest to the old woman's cave is where the stone
is located.