My 4 1/2 year old male Chihuahua (recently neutered) is generally very well behaved. He knows and obeys several commands, he never chews anything, aced house training, etc. However, he does suffer from separation anxiety and he also sometimes engages in what I can only think to call pouting. He will literally sit in a corner and ignore me (sometimes staring at me with pitiful puppy eye glances). He refuses to come when I call him and acts very cold towards me during these bouts and nothing I have done will make him stop. He used to only do it if he wanted my attention and I was busy with something and therefore ignoring him. Now I'm not sure what triggers it. As I write this, he's sitting under a chair in my room pretending that I don't exist. If other people are around he will curl up beside them and also ignore me. I used to try to comfort him but that never helped. Rather, I think it did the opposite, promoting the behavior. I notice he particularly does it when I have been away at school for a few months without seeing him as my housing situation doesn't allow me to have dogs. I know that he mopes from anywhere from a few days to a week when I have to leave home to return to school and leave him behind with my parents. Right now, he has an upset stomach--feeling sick also sparks his pouting. Should I just ignore him when he exhibits this behavior? What could be the cause? I worry it is a result of the coddling/spoiling he has received over the years (a behavior problem I'm working to curb in myself). Does anyone else have any experience with a dog pouting like a child would? Any advise is greatly appreciated.