No empty stomach..lol..she get plenty to eat..she is only a regular schelued meal plan and gets treats in between meals. I think I found out what it is. Like I said it was greenish the first time. I watch her close outside yesterday and she eats grass...i had noticed that she lays in the grass and chews at it but I thought she was just playing with it not eating it. But today i saw she was eating it. My husband says animals do this sometimes when they have a upset stomach. She hasn't vomited anymore. I'm feeding her exactly what the directions on the science diet food bag says and she eats twice a day with water by her at all times. Then she has this toy that I place treats in that she can play with and when the treats roll out she eats them. Thanks for your comments..Have a nice day..