We had the same problem when Inka was still a kitten. She got kitten food then, and was allowed to eat as much as she wanted. The problem was that Maya was overweight then, and on a diet for that . We solved the problem by giving the food zeperately. As Inka cannot climb on the kitchen counter (she is disabled), we decided to put Maya's food there. Inka got her food on the kitchen floor, and we took it away after 5 minutes. She soon learned that if she didn't eat when she got food, she had to eat it right away. This way there were NO leftovers for Maya to "steal" . I also gave Inka some extra food every time I was alone in the kitchen with her, while lazy Maya was napping