for three days now a strange cat has been circling my house wailing. Its not a fighting sound, almost a"crying" like she/he lost his best friend. My cat, a neutered female seems to be sympathetic since she is not chasing thee other cat off just stands off and watches. She has been very appreciative of me, more so that usual. . it does not seem to be hungry and I cant get it to come to me. I feel sorry for it but cant help it. What does this behavior indicate?