the other girl doesn’t have any black crap on any parts and still has some bugs but the lady bugs are reproducing and hopefully will take care of it before too long and the other plant will no longer be able to get her tainted or bugs move over to her ...
I had some aphids few weeks back I noticed them climbing up the stems and onto the leaves. I sprayed them with water mixed with dawn dish soap. They stopped appearing and are gone. It took a couple applications to get rid of them.