One of my dogs is whining for no apparent reason. She is a 12 year old whippet who became partially paralyzed (she can't really move her front two feet) because she ran into a glass door (last year at the end of October), but I doubt that has anything to do with it. She lays on her chair and whines quietly. It might be because she can sense that Alex, one of my other dogs, is sick, but I'm not sure. She sometimes does it when I pet her, so I don't think it's because she feels like she isn't getting enough attention. I don't know why she is doing this. Any ideas?