Well also, Teir's father didn't necessarily need to have that animal communication magic. It does seem to be teachable, like when he attempted to teach Ember. He could just have a strong inclination for picking up animal communication as a skill. If he was raised by an animal communicator and taught from a young age how to do that, I could easily see Kahvi pawning him off on some plains tribe guy to raise...and I think Tyldak would have agreed to that. I'm not sure if Windkin would have.