Isa has good intentions and she loves her children and want them to be happy. But she also had some personal reasons for getting Russ out of the way, and in her hurry she forgot to consider what it would mean for Evan. But all's well that ends well.
I don't think Russ' small lapse of 'presence of mind' will have any consequences other than his family being more aware of him.
I'm so pleased you like the mold joke, it's one of my favorites.
The twins snuck up on me, too, with the shared house idea.