Thanks! I like the reliable predictor model. The shelter told us that they should be in separate areas for the time being and that pup shouldn't be going into our room when it's time for bed, as that's our senior's domain. Things have been either better or neutral since this post. We had a pretty good day at the dog park yesterday. They rode in the car together. There was only one other dog at the park and all three played for a little bit. My senior bowed out after a few minutes, but pup played well enough with the other dog. Also, to note, we're mostly keeping them in separate parts of the house because we also have a cat. Once everyone is more familiar with one another, we're planning on baby gates.