OK, it's probably been discussed an awful lot, hence a slight hesitation to post my ideas about the TLJ world. But nevertheless, I'd like to try this one out:
To state some facts (and presumptions) first
We know that Faith and ZoŽ are sisters.
We know that April's mother is the (old) White of the Draic Kin.
It's been discussed a lot that Cortez is April's biological father.
It's possible (and in my opinion very plausable) that Helena Chang is ZoŽ's mother.
Could it be that Cortez is the father of all three above? It would explain April's shifting powers (as she is a full descendant of both Draic Kin [one of Stark, one of Arcadia]) and the dreaming powers of ZoŽ and Faith (with Cortez and the human mother Helena Chang [?]) It would rule out Gabriel as the biological father of ZoŽ, though. Poor bastard's been cheated by his wife - it fits Helena Chang's description as cold and pragmatic.
Cortez being her father explains why ZoŽ (and earlier: Faith) had to be OD'd to fulfill whatever they are destined to do in Dreamfall Chapters in Arcadia. It's just that Faith got a little stuck in her fantasy, creating some kind of Storytime/Guardian's Realm in the timeless. Faith's pleads to ZoŽ were answered when Helena Chang sent ZoŽ with a stronger dose not to move to Arcadia as quickly as she did the two times before, to help her daughter being pushed through to Arcadia in order to find out what she caused her youngest daughter to be in with the "bug" she planted on ZoŽ to initially spy on her - come on, you've gotta know what's sabotaging your company! !-
Notice that Faith is around as old as when Cortez "disappeared" to help out April "learn" to shift when the time was there, causing Helena not knowing what to do with Faith, locking her up in the virtual reality chamber of St. Petersburg.
It might explain why it was so hard for April to find Cortez earlier: he was busy with Faith as he didn't have someone as the father of ZoŽ to care for her, not trusting Helena with Faith (rightly so!). April could take care of herself in the time he wasn't there for her. He was only in Newport when April needed him there.
Cortez couldn't do anything against Helena's mistreatings of Faith, because of the unknown result of his falling out with the Green, McAllen.
It may sound far off, but (as many other theories) could be true....or have I missed something? It does open up the Arcadian abilities of April, ZoŽ and Faith...
On a less serious sidenote, doesn't the vagabond get lonely? His last known visit was nearly 300 years ago with Brian Westhouse who "wasn't supposed to be there."