I would love to hear your headcannons on Miss Nightjar and miss Thrush if your looking for things to do! Do you know why/or have a headcannon- (I don't know if it was said in the book), why they stopped having a loop together and miss Thrush now only co-runs that loop and has her own?
Okay!
First, I assume Nightjar is the oldest, and the thrush is a generation ahead. She probably interned in Nightjar's loop and became a professional caring for the more difficult and misbehaving children.
When she graduated, Millie T. created her own loop in London, but Miss Nightjar needed help with hers, and Millie was a pro at it, better than any inexperienced ymbryne in training. So the two started working together. Millie became co-leader of her old friend's loop, appearing there whenever Nightjar was overwhelmed.
Their separation is crucial, as ymbrynes are an extremely limited resource in the peculiar world. Two ymbrynes in a 2km loop is a real waste, especially if they're two powerful ymbrynes. Two separate ymbrynes are two loops, and more space for peculiars to live—them being separated is crucial to the local ymbryne shortage, especially after the Wights began killing many ymbrynes in Europe. The two of them being together in a single loop wasn't an extreme necessity, so this way was the most functional for both of them, instead of just one loop, crowded and unnecessarily with two ymbrynes, there were two loops each with one ymbryne and a small amount of peculiars inside.
