Hey! Okay! So!
Before I start, let's preface this with: take everything with a grain of salt, this is just one person's opinion. And I really do like what you're doing. I wouldn't be going into this much detail if I didn't.
You've laid a lot of groundwork, but the story so far isn't quite there. It's halting and it walks back on itself in order to lay more groundwork. I'd like to see you follow one thread for a while, whichever one that may be. If one of the other threads intersects with it, great, then that thread can get some development, too. But give me a reason to be invested in something before giving me another chapter of exposition on a new character.
So right now, you've got three chapters of foundation (which is fine), then five or six establishing chapters with the Gibsons, and another five or six chapters that more-or-less repeat the Gibson experience at the McMillan house, some very short vignettes, then a reasonably well-developed series of scenes with Zoe and Athena before we revert back to more establishing work at the lab while we introduce new characters. What I want to see is less establishment and foundation, and more experimentation with changes. I don't necessarily need a full scene about how Ms. Warren woke up with the dog's bollocks, I basically already got that scene a dozen times by now and the only new information is "animals are fair game." Show me why that's interesting. What changes in behavior has Lydia experienced? What changes in behavior has the dog experienced? Push forward to the next step, assuming that the reader already understands how step 1 works.
How is everyone affected by their changes? Are there more changes to come? How are they dealing with that? What actions are they taking differently now than they otherwise would? Give us some action to follow. Put our characters in predicaments. Explore how they manage those predicaments.
Like I said, the Zoe/Athena scene is a great start. That doesn't mean you have to focus on them on Day 2, you might prefer to focus on Jon or Sarah or Lydia. But give the reader something to chew on, and follow it through for a bit before moving on to the next thing.
And definitely keep writing, you've set up a fascinating premise, and I just want to see you explore it :)