Areth wasn't sure why this mare was so special. But he knew that there was something about her that made her different from every other horse in the stable. For one thing, he had witnessed Anya removing some strange, powerfully magical horseshoes from her, only to be apparently disappointed when nothing happened. Midnight was also more intelligent than she should be. The most intelligent horse breed was the Witch's Pony, created when witches took horse form and bred with horses. Almost every other horse in the stable was a Witch's Pony, but Midnight, an Arabian, was more intelligent than all of them. She clearly understood conversations to a level that a horse couldn't.
This and a few other things made Areth feel confident that Midnight was no horse. She was a transformed human. Apparently an important one. The identity of her, Areth didn't know yet. Hopefully he would figure it out. But even if he couldn't, he could keep her in horse form. All he had to do was make sure she was mated with each time she gave birth. In the meantime, he would send the news along to his superiors. The Copperstones were important in the Royalist movement. If the beloved daughter of the family, Anya, was so determined to tend to this specific horse, she was valuable.
Midnight whinnied tiredly as Areth brought Borealis back. Normally, Areth would give a longer time between mating sessions, but he had to make sure she was pregnant before Anya could turn her to her human form. Areth stood back and let Borealis do his work. Borealis mounted Midnight happily, making her neigh with pleasure. Areth stifled a snicker. At least Midnight seemed to be enjoying it. She should, since this was the rest of her life if Areth had anything to do with it.