I had kinda of a similar weird idea. Stick with me on this one. What if Tobias mated with another hawk and had babies and those babies also had the ability to morph? I keep having this weird scene in my head where Tobias' kids have human morphs and he's teaching them how to read and speak and whatnot.
I doubt that the morphing ability is genetic. However, it would be interesting if Tobias did find a female hawk and wanted to give her morphing ability.
<It worked with that buffalo, and it can work with her. All I have to do is sneak it out if Cassie's freezer, and get her to perch on it.>
That scenario might actually be believable, post buffa-human book. If there wasn't a Rachel/Tobias relationship going on, and maybe the hawk in book three didn't die.
I wonder why KA didn't bring the female hawk idea back after Tobias got more into being a bird. Some female hawk moves into his territory, and confliction ensues. There actually was a hawk that muscled into his meadow, but Tobias refused to do anything about it.
It would have made an interesting love triangle.