Aw, it's okay! You are not a bad parent. Exactly how overweight is she? What is her weight she would be best at?
Jackson is 15lbs and he eats 1/4 cup in the AM and 1/4 cup in PM of Acana Grasslands, but that is the grain free variety so it's a bit more calories, etc. He eats 1/2 cup total of kibble per day, plus some wet food and treats. And he stays at a perfect weight. He's also very active and athletic. Sneaking puppy food could do it because most are higher in fat, I believe. Like you said, just up the exercise and walks, and lower the food.
