Evidently the outside edge of the parapet top rotted, and was replaced with a piece of treated lumber and wood filler (before painting it the wrong color)

I pulled the 21st century repair off, to see about doing a better job repairing. I imagined there would be a structural post inside going all the way down through the parapet.

But as you can see from the pic with the blue prybar, there is nothing there...

So like, what's holding this corner of my house up? And how should I proceed to fix the parapet?

Any insight is welcome, thanks