Got another question. Grace is 3 years old and weighs almost 6 pounds. Cassie, on the other hand, is 7 months old and weighs almost 7 pounds!! The vet said to limit what she eats. I tried doing this, but then Grace would go to the food bowl and see that nothing was in there. I want Grace to eat if she is hungry, but how can I do that without Cassie gobbling it all down? Cassie gobbles down her bowl of food in the morning, and then goes and waits behind Grace. She knows that Grace will not finish her food, so when Grace leaves, she gobbles that down too. Help!