Block 9

This block starts off with a small pile of 1/2 square triangles. 

I then put together the pinwheel in the centre and the 4-patches in the corners.  Plus, I attached the 1/2 square triangles together.

Now the centre square-in-a-square is completed.  Plus, I've attached the posts for the red & 1/2 square triangle borders.

Then I added the red border.

Then the next border, and the next one...

And Tada!  Our next block is completed.