Just now it dawned on me that of the four times I've seen Aspen chase Pumpkin, three of them were when Pumpkin had just come in from outside. Aspen doesn't go outside. Could it be that when Pumpkin comes in he smells foreign to Aspen so she chases him? If so, any suggestions on what to do about it? Pumpkin just came in and I took the towel that I've been using to exchange their scents with and rubbed him down with it to try to get the outside smells off and put the inside smells back on. The fourth time she chased him was after Aspen had an encounter with another cat, Hobbs, through the screen porch screen and was very worked up so she chased Pumpkin a little.
I sure hope this is at the base of the problem and that rubbing him down when he comes in will help.
I sure hope this is at the base of the problem and that rubbing him down when he comes in will help.