Did the vet tell you that she was overweight or are you just comparing her to other yorkie puppies her age? You need to take into consideration the size of her parents (did you see them) and other factors in her final adult weight. She is only 15 weeks old and had a lot of growing still to do and needs proper nutrition. Did you vet give you a guideline and feeding schedule? Are you free feeding both your dogs? At this age she needs to be eating at least 3 times per day and I do not recommend free feeding because you cannot monitor the amount of food each of your dogs consume.
__________________ “Never argue with a fool, onlookers may not be able to tell the difference.”  Mark Twain |