I saw the iamge posted on the duplicate thread and it looks like it may be Spotted Spurge. There are several images in our database:
Spotted Spurge (Euphorbia maculata)
My suggestion would be to wait for a good rain or water the area thoroughly, then yank out the Spurge. If there are seeds present try not the shake the plants too much while pulling them out. I would finish by sprinkling some organic Preen or plain old corn gluten meal to prevent new plants in the area then mulch.
