Board Thread:Character Discussion/@comment-31427137-20170331142300/@comment-29754588-20170401031407

Eskaver wrote: The problem is that the writers would need to retcon that because as we know the curse didn't take Cruella, Ursula, and Ingrid back. If that was the case, then Neal and Hook could have stayed.

It's the problem with hindsight: it's 20/20.

In-show: Emma's the Savior, Henry's conceived here. (Despite Ursula and Cruella and Ingrid)

Out-of-show: Plot. The curse did not take Cruella and Ursula back because they were outside of Storybrooke. The curses' scope was in Storybrooke. As Emma and Henry leaves, the curse stops at the town line. Meaning Ursula, Cruella, Lily, the Dragon (whom all were outside of Storybrooke) stayed behind.

As for Ingrid, there's no indication whether she came by the (second) curse or not. When the heroes were tracking her Storybrooke alias of "Sarah Fisher", they did not find any, but Ingrid got that alias by herself, not the curse, so it is logical that "Sarah Fisher" wasn't in the log.