I have only had my yorkie for a few months now and sometimes he seems to do that. I also have a Boxer who seems to do it a lot more (a few times a month). Sometimes I think that they do it when there stomach is empty or if they are very excited. My Boxer use to do it in the mornings before he would eat. I usually do not feed my dogs until every human in the house has ate ( I am one of those pack leader dog person). What I do now is give them some liver treats packed into their bones while we eat and them feed them. I think that in my case my Boxer had an empty stomach. I feed my yorkie 3 meals a day and my boxer 3 small meals a day. I also think that sometimes fear, excitement, empty stomach, or pain can make them vomit. So you just have to look at your dog and try to see what he is doing before he vomits. Good Luck. |